Srinivas

Students can go through AP State Board 9th Class Physical Science Notes Chapter 12 Units and Graphs to understand and remember the concept easily.

AP State Board Syllabus 9th Class Physical Science Notes Chapter 12 Units and Graphs

→ A unit is a standard measure used for comparing measurements.

→ Units should be placed right side of the magnitude of every physical quantity.
For Example 2 kilograms, 100 grams.

→ The main fundamental quantities are mass (m), length (l), time (t).

→ Fundamental quantities are those physical quantities that cannot be expressed in terms of other quantities.

→ Fundamental quantities are also called base quantities.

→ Scientists evolved different types of measuring systems such as FPS, CGS, MKS, etc.

• FPS System: Foot – Pound – Second.
• CGS System: Centimeter – Gram – Second.
• MKS System: Meter – Kilogram – Second.

→ SI System is an International System of units.

→ In addition to mass, length, and time some other fundamental quantities were added to the SI system.

→ Units in SI System:

• Length – Meter (m)
• Mass – Kilogram (kg)
• Time – Second (s)
• Electricity – Ampere (A)
• Light intensity – Candela (Cd)
• Quantity of substance – Mole (Mol)
• Temperature – Kelvin (K)
• Plane angle – Radian (rad)

→ The quantities that are obtained by combining fundamental quantities either by multiplication or division or both operations are called derived quantities.

→ Some derived quantities are speed, velocity, area, volume, density, acceleration, force, pressure, etc.
→ Derived units are units of measurements derived from the fundamental units.

→ Some examples of derived units are

• Area – m²
• Volume – m³
• Speed – m/s
• Velocity – m/s
• Acceleration – m/s
• Force – \(\frac{\mathrm{kg}}{\mathrm{m} / \mathrm{s}^{2}}=\frac{\mathrm{kg} \cdot \mathrm{s}^{2}}{\mathrm{~m}}\) , etc.

→ We need to convert units of a physical quantity into a single system to compare both values.
For example: To compare 1500 m and 1.5 km Convert km into meters.
Then 1500 m = 1500 m, 1.5 km = 1500 m
Hence both values are equal.

→ 1000 m = 1 km
1000 is prefixed to meter called as ‘Kilo’

→ 1 km/hr = \(\frac{5}{18}\)m/s

→ Meter is the distance travelled by light in a vacuum in \(\frac{1}{299792458}\) seconds

→ There are some rules to follow while writing units.

→ A pictorial form of representation that shows the relation between two quantities can be called a graph.

→ The expressed quantity depends on the independent and dependent variables taken for plotting the graph.

→ Generally, independent variables are controlled or decided by us, but dependent variables are changed due to the change independent variable.

→ The thick horizontal line on the graph paper is called X-axis.

→ The thick vertical line on the graph paper is called Y-axis.

→ The Independent variable should be taken on the x-axis, whereas the dependent variable is on the y – axis.

→ The range is the difference between the highest value and lowest value of the data.
Range = highest value – lowest value.

→ Scale on X-axis = \(\frac{\text { Range }}{\text { The number of grids on } \mathrm{X} \text { -axis }}\)
Scale on y-axis = \(\frac{\text { Range }}{\text { The number of grids on } \mathrm{Y} \text { -axis }}\)

→ Axes should be named with the quantity taken on it along with their units.

→ The values taken as pairs such as (x₁, y₁), (x₂, y₂), are called data points.

→ If a graph is curved in shape, it is called a curved graph.

→ If a graph is a straight line, it is called a straight line graph.

→ Both curved, straight-line graphs are called line graphs.

→ Hooke’s Law: Elongation of the spring is proportional to mass.
The graph of extension and mass is a straight-line graph and it indicates the relationship of direct proportional between extension and mass.

→ Direct proportion:

• The initial values should be counted as “0”.
• The ratio of any pair has to be constant.
• If the value of one quantity increases, the value of the second quantity also increases.

→ Inverse proportional:

• The value of one quantity should be “0”, the value of the second quantity cannot be defined, it can be infinite.
• The product of any two pairs should be constant.
• The value of one quantity increases, the value of the second quantity should be decreased.

→ Pressure ∝ \(\frac{1}{\text { Volume }}\) [inversely proportionally]
The graph of pressure and volume is parabolic in shape.

→ Slope of the straight line = \(\frac{\text { Change in } y \text { -coordinates }}{\text { Change in } x \text { -coordinates }}=\frac{\text { rise }}{\text { run }}\) (or) tan θ = \(\frac{\Delta y}{\Delta x}\)

→ The slope of the graph is denoted by “m”.

→ The slope of the straight line increases along with the increase of angle.

→ The slope of the X-axis is zero.

→ Slope can be determined by coordinates of x, y, or by the angle of a straight line with the X-axis.

→ A curved line graph has an infinite number of slopes.

→ We can calculate the slope at any point on the curve by drawing a tangent to it.

→ The ratio of the Y and X-axis represents slope.

→ The product of quantities on the Y and X-axis is said to be an area of the graph.

→ Unit: A unit is a standard measure used for comparing measurements.

→ Fundamental: Fundamental quantities are those physical quantities that quantities cannot be expressed in terms of other quantities.

→ Basic quantities: Fundamental quantities are also called basic quantities.

→ FPS: Foot, Pound, Second.

→ CGS: Centimeter, Gram, Second.

→ MKS: Meter, Kilogram, Second.

→ SI System: International System of units.

→ Derived quantities: The quantities that are obtained by combining fundamental quantities either by multiplication or division or both operations are called derived quantities.

→ Some fundamental: Length, Mass, Time, Electricity, Light intensity, Quantity of quantities substance, Temperature, Plane angle.

→ Some derived quantities: Area, Volume, Density, Velocity, Acceleration, Force, Pressure.

→ Fundamental Units: Meter, Kilogram, Second, Ampere, Candela, Mole, Kelvin, Radian.

→ Derived Units: Derived units are units of measurement derived from the fundamental units. m², m³, kg/m³, m/s, m/s².

→ Meter: Meter is the distance travelled by light in a vacuum in \(\frac{1}{299792458}\) seconds

→ Graph: A pictorial form of representation that shows the relation between two quantities can be called a graph.

→ Independent: The variable which is controlled or decided by us to plot a graph variable is called the independent variable.

→ Dependent variable: The variable which is changed due to the change in the independent variable is called the dependent variable.

→ Grids: Grids of one square centimeter form by the intersection of thick lines and one square millimeter grid form with the intersection of thin lines in graph paper.

→ X-axis: The thick horizontal line on the graph paper is called X-axis.

→ Y-axis: The vertical thick line is called Y-axis.

→ Range: The highest value – the lowest value.

→ Scale: The interval taken to point the values on the axes is called scale.
Scale = \(\frac{\text { Range }}{\text { The number of grids on the axis }}\)

→ Data points: The values are to be taken as pairs in order to mark them as points on the graph such as (x, y) is called data points.

→ Curved line graph: If the line in a graph is in a curved shape, then the graph is called a curved line graph.

→ Straight-line graph: If the line in a graph is a straight line, then the graph is called a straight-line graph.

→ The slope of a straight: The ratio between the change in y-coordinates and the line graph x – coordinates gives the slope of the straight-line graph.

→ Slope = \(\frac{\text { Change in } y \text { -coordinates }}{\text { Change in } x \text { -coordinates }}=\frac{\text { rise }}{\text { run }}\) (or) tan θ = \(\frac{\Delta y}{\Delta x}\)
The slope is denoted with ‘m’.

→ Area of graph: The product of the physical quantity of the Y-axis and X-axis is said to be an area of the graph.


→ Robert Hooke:

• Born: 28th July (O.S. 18 July) 1635
• Died: 3rd March 1703 (aged 67)
• Nationality: English
• Alma mater: Wadham College, Oxford
• Known for: Hooke’s law, Microscopy,
• Coining the word ‘cell’
• Fields: Physics and Chemistry
• Institutions: Oxford University Academic
• Advisors: Robert Boyle
• Influences: Richard Busby

Students can go through AP State Board 10th Class Biology Notes Chapter 10 Natural Resources to understand and remember the concept easily.

AP State Board Syllabus 10th Class Biology Notes Chapter 10 Natural Resources

→ The earth’s natural resources are water, soil, minerals, fuels, plants, and animals.

→ Resources that can be replaced after they are used are called renewable resources.

→ Resources that cannot be replaced at all after they are used are called non-renewable resources.

→ Percolation tanks are normally earthen dams with masonry structures where water may overflow.

→ Conservation is the practice of caring for the resources so all living things can benefit from them now and in the future.

→ Management of resources is essential for their conservation and restoration.

→ Resources are usually local specific and local people need to have control over them.

→ People need to be motivated to reduce pressure on the environment by reducing the utilization of resources and reusing some of them.

→ Less than 0.01% of the water on the earth is surface water, but if used judiciously, shall last for a long time.

→ Drip irrigation can reduce water consumption by 70%.

→ Sustainable forestry practices are critical for ensuring resources well into the future.

→ Contour strip cropping helps in reducing soil erosion.

→ Biodiversity is the variety of living things that populate the earth.

→ We need to protect biodiversity to ensure we have plentiful and varied food sources, medicines, etc.

→ Fossil fuels were produced from the remains of ancient plants and animals.

→ We must use our resources judiciously especially fossil fuels, coal, and petroleum as they will be ultimately exhausted.

→ Scientists are trying to produce renewable biofuels to power cars and trucks.

→ Seeds from the Jatropha curcas plants are used for the production of biofuel.

→ Earth’s supply of raw mineral resources is in danger.

→ Four R’s help to save the environment. They are Reduce, Reuse, Recycle and Recover.

→ Interstate and intercountry disputes should not hamper the availability of a resource.

→ International Union for the Conservation of Nature (IUCN) works to protect wildlife and habitats.

→ Percolation tank: These are the structures for recharging groundwater, normally earthen dams.

→ Micro-irrigation: Irrigating crop fields with less amount of water by drip irrigation and sprinkler irrigation. Water conservation method.

→ Borewells: A well constructed by boring a vertical hole.

→ Sustainable development: When we use the environment in ways that ensure we have resources for the future it is called sustainable development.

→ Biofuels: A fuel derived from living matter (biological raw materials).

→ Contour strip farming: Forming by planting several crops, such as corn, wheat, and clover, in alternating strips across a slope or across the path of the prevailing wind.

→ Dyke Management: Dykes or barriers, nearly 30 cm thick of brick – cement or stone cement barriers, extending down to the compact bedrock with mud or clay fillings were built in underground streams to tap groundwater optimally.

→ Open dug well: A well made by excavating with hand tools or power machinery Instead of by drilling or driving.

→ Natural resources: Anything In the environment which can be used is called a natural resource.

→ Conservation: The protection of natural things such as animals, plants, forests, etc., to prevent them from being spoiled or destroyed.

→ Renewable resources: Any natural resource that can be replenished or replaced naturally after they are used is called renewable resources.
e.g.: Soil, water, plants, etc.

→ Non-renewable resources: Any natural resource that cannot be replaced at all or takes a long time for their formation are called non-renewable resources. e.g.: Coal, petroleum, natural gas, etc.

→ Selective harvesting: The practice of removing Individual plants or small groups of plants leaving other plants standing to anchor the soil is called selective harvesting.

→ Biodiversity: The variety of living things that populate the earth.

→ Jean-Baptist Joseph Fourier (1768 – 1830):

• Jean-Baptist Joseph Fourier was a French mathematician and physicist born in Auxerre and best known for initiating the investigation of the Fourier series and their applications to problems of heat transfer and vibrations.
• He was the First one to spoke about the Green House Effect in 1827.
• Gases like Carbon dioxide, Nitrogen oxides, Chlorofluorocarbons, Methane, etc. are called greenhouse gases.
• They warm up the earth and when fossil fuel is burnt Carbon dioxide is released.

Students can go through AP State Board 9th Class Physical Science Notes Chapter 11 Sound to understand and remember the concept easily.

AP State Board Syllabus 9th Class Physical Science Notes Chapter 11 Sound

→ Sound is produced by a vibrating body.

→ Sound is transmitted through a medium and received by our ears.

→ A sound is a form of energy.

→ Sound travels through disturbances in the form of waves.

→ The matter or the substance through which sound is transmitted is called the medium. If the particles of the medium vibrate along the direction of the wave, then the wave is called a longitudinal wave. Sound waves are longitudinal.

→ Longitudinal waves consist of compressions and rarefactions.

→ The region of the high density of particles in the medium during propagation of sound is called compression and low-density regions are called rarefaction.

→ The distance between two consecutive compressions or two successive rarefactions is called the wavelength of a sound wave.

→ If the particles of the medium vibrate perpendicular to the direction of the wave, then the wave is called a transverse wave.

→ The maximum variation in density or pressure from the mean value is called amplitude. The number of oscillations of the density of the medium at a place per unit time is called the frequency of the sound wave.

→ The time taken to complete one oscillation of the density of the medium is called the time period of the sound wave.

→ Frequency and time period are related as T = 1/u or o = 1/T

→ The distance by which a point on the wave, such as a compression or rarefaction travel in unit time is called the speed of the sound wave.

→ The relation between the speed of a sound wave, wavelength, and frequency is v = uA.

→ The sounds which produce pleasing effects on the ear are called musical sounds, while the sounds which produce unpleasant effects are called noises.

→ The characteristics by which one can distinguish a musical note from another are pitch, loudness, and quality.

→ Pitch is a characteristic of sound which distinguishes between a shrill sound and a deep, low sound.

→ The loudness of sound is defined as the degree of sensation produced in the ear, measured in decibels.

→ The quality of sound is the characteristic that enables us to distinguish between musical notes emitted by different musical instruments.

→ Sound reflects as light reflects.

→ A reflection of sound, arriving at the listener in more than 0.1 s after the direct sound is called an echo.

→ A reflection of sound, arriving at the listener in less than 0.1 s after the direct sound is called reverberation.

→ The human ears are able to hear sound in a frequency range of about 20 Hz to 20 kHz. Sounds of frequency less than 20 Hz are known as infrasonic sounds.

→ Sounds of frequency higher than 20 kHz are known as ultrasonic sounds.

→ Ultrasonic waves are used in drilling holes or making cuts of different shapes, cleaning, detection of defects in metals, in the medical field to imaging of organs, surgeries, etc.

→ SONAR stands for Sonographic Navigation and Ranging.

→ SONAR is equipment or a system for finding objects underwater using sound waves.
→ Mechanical energy: Energy produced by mechanical means like pushing, pulling, beating, vibrating, etc. is known as mechanical energy.

→ Tuning fork: A tuning fork is an acoustic resonator. It is a steel bar, bent in U-shape, with a handle at the bend. It resonates at a specific constant pitch when set into vibration by a string with a rubber hammer.

→ Longitudinal wave: If the particles of the medium vibrate along the direction of the wave, then the wave is called a longitudinal wave.

→ Transverse wave: If the particles of the medium vibrate perpendicular to the direction of the wave, then the wave ¡s called a transverse wave.

→ Compression: Compression is the region where density, as well as the pressure of particles in the medium, is high.

→ Rarefaction: Rarefaction is the region where density, as well as the pressure of particles in the medium, is low.

→ Crest: Crest is a point where the amplitude of a wave is maximum in a transverse wave.

→ Trough: A trough is a point where the amplitude of a wave is minimum in a transverse wave.

→ Pressure: Pressure is force per unit area applied in a direction .perpendicular to the surface of an object. The SI unit of pressure is the newton per square meter, which is called the pascal (Pa) after the seventeenth-century philosopher and scientist Blaise Pascal.

→ Wavelength: The distance between two consecutive compressions or two consecutive rarefactions is called the wavelength of a sound wave.

→ Amplitude: The maximum variation in density or pressure from the mean value is called amplitude.
(or)
The maximum disturbance of the particles of a medium from their mean position is called amplitude.

→ Frequency: The number of oscillations of the density of the medium at a place per unit time is called frequency.

→ Pitch: Pitch is a characteristic of sound which distinguishes between a shrill sound and a deep, low sound.

→ Loudness: Loudness of sound is defined as the degree of sensation produced in the ear.

→ Quality of sound: The quality of sound is the characteristic that enables us to distinguish between musical notes emitted by different musical instruments.

→ Echo: A reflection of sound, arriving at the listener in more than 0.1 s after the direct sound is called an echo.

→ Reverberation: A reflection of sound, arriving at the listener in less than 0.1 s, after the direct sound is called reverberation.

→ Infrasonic: Sound of frequency less than 20Hz is known as infrasonic sound.

→ Sonic: Of or relating to audible sound. e.g: a sonic wave.

→ Ultrasonic: Sound of frequency greater than 20 kHz is known as ultrasonic sound.

→ SONAR: SONAR stands for Sonographic Navigation And Ranging. It is equipment or a system for finding objects underwater using sound waves.

→ Heinrich Rudolf Hertz:
Heinrich Rudolf Hertz was born on 22 February 1857 in Hamburg, Germany, and educated at the University of Berlin. He was the first to conclusively prove the existence of electromagnetic waves. He laid the foundation for the future development of radio, telephone, telegraph, and even television. He also discovered the photoelectric effect which was later explained by Albert Einstein. The SI unit of frequency was named Hertz in his honor.

Students can go through AP State Board 10th Class Biology Notes Chapter 8 Heredity to understand and remember the concept easily.

AP State Board Syllabus 10th Class Biology Notes Chapter 8 Heredity

→ Variations arising during the process of reproduction can be inherited.

→ Variations may lead to increased survival of the individuals.

→ Gregor Johann Mendel known as the father of genetics started working on the problem of how variations were passed from one generation to another.

→ Mendel had chosen 7 pairs of contrasting characters in pea plants for his study: flower colour, flower position, seed colour, seed shape, pod colour, pod shape and stem length.

→ The Pea plant is an annual plant that contains vitamins A, C, E, K and B and minerals like Ca, Fe, Mn. Mg, P, S and Zn.

→ Cross-pollinating a pure breed of yellow and green gave all pea seeds in the F₁ generation were yellow.

→ On self-pollination plants of Ft generation, they gave about 75% yellow seeds and 25% green seeds in the F₂ generation.

→ The phenotype ratio of F₂ plants is 3: 1.

→ In the F₂ generation out of 75%, 25% were pure yellow seeds, 50% were yellow seeds but green was a recessive factor. The remaining 25% were pure green. This is called genotype. The ratio is 1: 2: 1.

→ In the F₃ generation, Mendel self-pollinated F₂ generation pea plants and found that about 25% gave only yellow seed giving pea plants, the rest of the yellow pea plants gave about 75% yellow and about 25% green seed giving pea plants.

→ And the set of green peas gave only green seed giving pea plants.

→ Every pea plant has two factors that are responsible for producing a particular property or trait called “allele”.

→ During sexual reproduction, one factor from each parent is taken to form a new pair in the offspring.

→ Crossing yellow and green seeds produced all yellow seeds because yellow is the dominant factor.

→ In the inheritance of more than one pair of characters, the factors for each pair of characters assort independently of the other pairs. This is known as Law of independent assortment.

→ The factors which are responsible for the character or trait of an organism, are now named genes.

→ Law of dominance states that among a pair of alleles for a character only one expresses itself in the first generation, as one of the alleles is dominant over the other.

→ The Law of segregation states that every individual possesses a pair of alleles for any particular trait and that each parent passes a randomly selected copy (allele) of only one of these to its offspring.

→ Traits that may be passed from one generation to the next are called heritable traits.

→ Sexual reproduction and errors in DNA copying lead to variations in offspring in a population.

→ Change in the frequency of genes in small populations is known as genetic drift.

→ Jean-Baptist Lamarck was the first person to propose the theory of evolution. He proposed the inheritance of acquired characters.

→ Characters that are developed during the lifetime of an organism are called acquired characters.

→ August Weismann proved that bodily changes are not inherited.

→ Charles Darwin proposed the famous theory of evolution called Natural Selection.

→ Transmission or passing of characters or traits from parent to offspring is called Heredity.

→ The process in which traits are passed from one generation to another generation is called Inheritance.

→ Gene is a segment of a nucleic acid called DNA which is present in the nucleus of every cell.

→ The detailed structure of DNA was discovered by Francis Crick and James Waston.

→ Each human cell contains 23 pairs of chromosomes out of which 22 pairs of chromosomes are autosomes.

→ 1 pair of chromosomes are called allosomes or sex chromosomes.

→ Gametes produced by women will be with only ‘X’ chromosomes.

→ Gametes produced by man will be of two types one with X chromosomes and the other with Y chromosomes.

→ If the sperm carries the X chromosome and fertilizes the ovum with the X chromosome, the resultant baby will have XX condition. So the baby will be a girl.

→ If the sperm carries the Y chromosome and fertilizes the ovum with the X chromosome, the resultant baby will have XY condition. So the baby will be a boy.

→ According to the theory of Natural selection, nature only selects or decides which organism should survive or perish in nature.

→ Alfred Russel Wallace concluded that natural selection contributed to the origin of new species.

→ Walter Setton and Thomas Morgan conducted experiments on (fruit fly) Drosophila melanogaster about sex-linked inheritance in them.

→ In the struggle for existence, only the fittest can survive.

→ Darwin published his famous book The origin of species’ in 1859.

→ The small changes within the species are called Micro Evolution.

→ The changes beyond the species are called Macro Evolution.

→ The organs which perform different functions but have similar structures and origins are called homologous organs, eg.: Forelimb of whale, a wing of bat. leg of cheetah, the claw of a mole and the hand of man.

→ The organs which are similar in appearance and function, but have different structures and origins are called analogous organs, eg.: Wings of butterflies, bats and birds.

→ Embryology is the study of the development of an organism from egg to the adult stage.

→ The developmental stages of different animals reveal that they are evolved from common ancestors.

→ Preserved traces of living organisms are called fossils.

→ The study of fossils is called palaeontology.

→ Archeopteryx is recognised as connecting link between Aves and reptiles.

→ Human evolution is the evolutionary process leading up to the appearance of a modern human being.

→ There are nearly 180 vestigial organs are present in human beings.

→ Variations: Differences in characters within closely related groups of organisms are referred to as variations. They result in organisms belonging to a species being different from each other.

→ Offsprings: The organism or organisms resulting from sexual or asexual reproduction. The product of the reproductive processes of an animal or plant.

→ Traits: A distinguishing characteristic or quality, typically one belonging to a person or animal.

→ Phenotype: It is the composite of an organism’s observable characteristics or traits such as its morphology, development, etc.

→ Genotype: It Is the genetic makeup of an individual usually with reference to a specific characteristic tinder consideration.

→ Heterozygous: It refers to have two different alleles for a single trait.

→ Homozygous: Homozygous refers to have two identical alleles for a single trait.

→ Independent assortment: It states that allele pairs separate independently during the formation of gametes.

→ Allele: It is an alternative form of a gene that is located at a specific position on a specific chromosome.

→ Heredity: The process of acquiring characters or traits from parents to offspring.

→ Autosomes: An autosome is any chromosome that is not a sex-determining chromosome. In humans, there are 22 Pairs of autosomes.

→ Allosomes: Sex determining chromosomes that differ from an ordinary autosome in size, form and behaviour human sex chromosomes are a typical pair of sex chromosomes.

→ Natural selection: Darwin’s most famous theory. A process resulting in the survival of those individuals from a population of animals or plants that are best adapted to the prevailing environmental conditions.

→ Analogous organs: Organs that have similar appearance and functions but have different structures and origins. eg.: Wings of butterfly, of a bat and of a bird.

→ Embryological: Evidence available from the embryonic development of evidence organism for organic evolution.

→ Human evolution: It Is the evolutionary process leading to the appearance of anatomically modern humans.

→ F₁ Generation: FIrst filial or progeny of first-generation. The first generation was produced by a cross and consisting of hybrid organisms.

→ F₂ Generation: The generation produced by interbreeding individuals of an F₁ generation.

→ Gene: A gene is the basic physical and functional unit of heredity. Gene is a working subunit of DNA.

→ Dominant gene: Gene that produces the same phenotype in the organism whether or not its allele is identical.

→ Recessive gene: Gene that produces its characteristic phenotype only when its allele is identical.

→ Inheritance: The process in which traits are passed from one generation to another generation.

→ Evolution: Evolution is a change in heritable traits of biological populations over successive generations.

→ Genetic drift: It is the change ¡n the frequency of genes in a small population.

→ Acquired characters: The characters that are developed during the lifetime of an organism are called acquired characters.

→ Microevolution: Evolutionary change within a species or small group of organisms, especially over a short period.

→ Macroevolution: Macroevolution generally refers to evolution above the species level.

→ Homologous organs: The organs which perform different functions but have similar structures and origins. eg.: Wing of the bat, the flipper of a seal, front leg of a horse, an arm of a man, etc.

→ Subtle: So delicate or precise as to be difficult to analyse or describe.

→ Ancestors: Ancestors ¡s any person from whom one is descended.

→ FossIl: These are evidence of ancient life forms which have been preserved by natural processes.

→ Palaeontology: The study of fossils is called Palaeontology.

→ Vestigial organs: The organs which are not useful in animals are called vestigial organs.

→ Heredity:

→ Monohybrid cross:

→ Sex Determination in Human:

→ Mechanism of Heredity:

→ Genetic Drift:

→ Human Evolution:

→ Genetic footprints of Humans hundreds/thousands of years ago Earliest members are in Africa:

→ Gregor Johann Mendel (1822 – 1884):

• Gregor Johann Mendel was considered as ‘Father of Genetics’.
• He was the first person to trace the characteristics of successive generations of a living thing.
• He was an Augustinian monk. So he did all his experiments in the monastery garden.
• Mendel made many careful observations of plants and chose pea plants for his experiments through which he made the law of inheritance.
• His work was so brilliant and unprecedented at the time it appeared, that it took thirty-four years for the rest of the scientific community to catch up to it.

Students can go through AP State Board 9th Class Physical Science Notes Chapter 10 Work and Energy to understand and remember the concept easily.

AP State Board Syllabus 9th Class Physical Science Notes Chapter 10 Work and Energy

→ Two conditions need to be satisfied in order to say that work has taken place. One is a force that should act on the object and another is the object must be displaced or there must be a change in the position of the object.

→ Work W = F × s (This formula for work is used in only translatory motion of the object)

→ Units of work ‘N-m’ (or) ‘Joule’.

→ Work has only magnitude, no direction. So work is a scalar.

→ If a force acting on an object and displacement are in opposite directions, then the work done by the force is taken as negative.

→ If work has a positive value, the body on which the work has been done would gain energy.

→ If work has a negative value, the body on which the work has been done losses energy.

→ The capability of doing work by an object is defined as the energy of the object.

→ The energy of an object depends on the position and state of the object which is doing work.

→ Whenever work has been done on an object, its energy either increases or decreases,
i. e., energy transfer takes place from one object to another object.

→ The sun is the biggest natural and primary source of energy.

→ Energy can exist in several forms like mechanical energy, light energy, thermal energy, sound energy, electrical energy, magnetic energy, etc.

→ The main source of energy for the human body is food.

→ The energy possessed by an object due to its motion is called kinetic energy.
K.E = \(\frac{1}{2}\)mv²

→ The K.E. of an object increases with its speed.

→ The energy possessed by an object because of its position or shape is called its potential energy.
P.E. = mgh

→ The sum of the kinetic energy and the potential energy of an object is called it’s mechanical energy.

→ Energy will be converted from one form to other forms in nature.

→ The law of conservation of energy states that the energy neither is created nor destroyed. It can only be changed from one form to another.

→ Power is defined as the rate of doing work or the rate of transfer of energy.
Power (P) = \(\frac{\text { Work }(W)}{\text { Time }(t)}\)

→ The unit of power is ‘watt’.

→ Work: A work is said to be done when the following conditions are satisfied.

• A force should act on the object
• The object must be displaced or there must be a change in the position of the object

(or)
Work is equal to the product of the force applied and displacement. W = F × s

→ Energy: The capability of doing work by an object is known as the energy of the object.

→ Transfer of energy: Energy transfer will take place from one object to another object when work has been done by the object.

→ Sources of energy: Sun is the main natural source of energy. There are so many derived sources of energy due to the sun. Some artificial sources of energy are thermal energy, electrical energy, etc.

→ Conservation of energy: Energy can neither be created nor destroyed. It can only be changed from one form to another. This is called the law of conservation of energy.

→ Kinetic energy: The energy possessed by an object due to its motion is called kinetic energy.
K.E. = \(\frac{1}{2}\)mv²

→ Potential energy: The energy possessed by an object because of its position or shape is called its potential energy.
P.E. = mgh

→ Mechanical energy: The sum of kinetic energy and the potential energy of an object is called it’s mechanical energy.

→ Gravitational potential: An object increases its energy when it is raised through a height, because of the work done on the object against gravity acting on it. The energy of such an object is known as gravitational potential energy.

→ Power: Power is defined as the rate of doing work or the rate of transfer of energy.


→ Gaspard-Gustave Coriolis:

• Coriolis was born in Paris on 21 May, 1792.
• He was a French mathematician and physicist.
• He worked to extend the notion of kinetic energy and work to rotating systems.

Students can go through AP State Board 9th Class Physical Science Notes Chapter 9 Floating Bodies to understand and remember the concept easily.

AP State Board Syllabus 9th Class Physical Science Notes Chapter 9 Floating Bodies

→ Density is defined as mass per unit volume. Mass
Density = \(\frac{\text { Mass }}{\text { Volume }}\)
Unit of density = gm/cm3 or kg/m3

→ The relative density of an object is the ratio of the density of the object to the density of the water.
Relative density of an object = \(\frac{\text { Density of the object }}{\text { Density of water }}\)

→ Experimentally relative density of a solid object = \(\frac{\text { Weight of the object }}{\text { weight of water equal to the volume of the object }}\)

→ Relative density of liquid = \(\frac{\text { Weight of liquid }}{\text { Weight of the same volume of water }}\)

→ Lactometer is used to measure the purity of milk.

→ A hydrometer is used to measure the relative density of liquids.

→ Objects having a density less than the liquid in which they are immersed float on the surface of the liquid.

→ Every fluid exerts upward pressure on the objects immersed in them. If the upward pressure is less than the gravitational force on the object, the object sinks otherwise it floats on the liquid.

→ The pressure exerted by the air in our surroundings is known as atmospheric pressure. Atmospheric pressure P₀ = ρhg.

→ The barometer is used to measure the atmospheric pressure at a place.

→ Pressure at a depth ‘h’ in a liquid P = P₀ + ρhg
P₀ = Atmospheric pressure ; ρ = density of the liquid h = depth ; g = acceleration due to gravity

→ Buoyancy is the upward force exerted by the liquid on any object less dense than itself.

→ When an object is immersed in a fluid, it appears to lose weight (because of buoyancy).

→ The apparent loss of weight of an object, which is immersed in a liquid, is equal to the weight of the liquid displaced by the object. (Archimedes principle)

→ When an object floats on the surface of a liquid, it displaces a weight of liquid equal to its own weight.

→ The pressure exerted by a liquid increases with depth below the surface of the liquid.

→ Pascal’s principle states that external pressure applied to an enclosed body of fluid is transmitted equally in all directions throughout the fluid volume and the walls of the containing vessel.

→ Density: When two objects of equal volume are considered the object
with higher mass is said to be a dense object. Density is defined as mass per unit volume.
∴ Density = \(\frac{\text { Mass }}{\text { Volume }}\)
Unit of density gm/cm (or) kg/rn3.

→ Relative density: Relative density is the ratio of the density of an object to the density of water.
Relative density of an object = \(\frac{\text { Density of the object }}{\text { Density of water }}\)
(or)
Relative density of an object = \(\frac{\text { Weight of the object }}{\text { weight of water equal to the volume of the object }}\)

→ Lactometer: Lactometer is a device used to measure the purity of milk. It works on the principle of relative density.

→ Hydrometer/ Densitometer: Hydrometer/Densitometer ¡s an instrument used to measure the relative density of any liquid.

→ Atmospheric pressure: Air in our surroundings exerts pressure on the surface of the earth called atmospheric pressure.
Atmospheric pressure P₀ = ρhg
ρ = average density of air
h = height of the atmosphere
g acceleration due to gravity

→ Barometer: Atmospheric pressure can be measured using a barometer. The first barometer was invented by ‘Torricelli’, using mercury. The height of the mercury column at normal atmospheric pressure is 76 cm.
The increase or decrease in the height of the mercury column indicates sudden changes in the atmosphere.

→ Buoyancy: The upward force that a fluid exerts on an object less dense than itself.
(or)
Buoyancy is the ability of an object to float in a liquid.

→ Archimedes principle of buoyancy: An object in a fluid is buoyant up by a force equal to the weight of the fluid the object displaces.

→ Archimedes:

• Archimedes was born in 287 BC and died in 212 BC.
• He was a Greek mathematician, physicist, engineer, inventor, and astronomer.
• He is well known for his Archimedes principle.
• Among his advances in physics are the foundations of hydrostatics.

Students can go through AP State Board 10th Class Biology Notes Chapter 7 Coordination in Life Processes to understand and remember the concept easily.

AP State Board Syllabus 10th Class Biology Notes Chapter 7 Coordination in Life Processes

→ Every life process is dependent on others to keep the body in good condition.

→ When glucose levels in the blood fall we get hunger pangs in the stomach.

→ The hormone ghrelin secreted in the stomach is responsible for hunger generating sensations.

→ Ghrelin is secreted from certain cells in the wall of the stomach.

→ Hormone leptin suppresses hunger.

→ Interactions between the senses of taste and smell enhance our perceptions of the foods we eat.

→ Russian scientist Ivan Pavlov has conducted experiments on conditioned reflexes.

→ Taste can be identified easily when the tongue is pressed against the palate.

→ Food in the mouth has to be broken down into tiny pieces to increase the surface area for the action of substances that aid in digestion.

→ The dental formula of human beings is \(\frac{2,1,2,3}{2,1,2,3}\)

→ The fifth cranial nerve controls the movement of muscles in the jaw.

→ The mechanism for swallowing is also under nervous coordination and its control center is in the brain stem.

→ The nature of saliva is alkaline.

→ Saliva is secreted by the action of the autonomous nervous system from salivary glands. The chewing of food in the mouth forms a slurry mass called a bolus.

→ The wall of the esophagus is made up of inner layer circular muscles and the outer layer longitudinal muscles.

→ Contraction and relaxation of the muscles present in the esophagus resulting in wave-like movements called peristaltic movements.

→ The food from the esophagus reaches the stomach by peristaltic movements.

→ The partially digested food present in the stomach is known as chyme.

→ Pyloric sphincter present at the opening of the stomach and small intestine releases a small amount of chyme into the duodenum.

→ Reverse peristalsis occurs in ruminating animals like cows.

→ The gastric juice produced by the stomach contains mucus, hydrochloric acid, and pepsin. Food is completely digested in the small intestine.

→ Absorption of nutrients by villi takes place in the small intestine.

→ The neural apparatus of our digestive tract comprises a vast and complicated network of neurons called the second brain or enteric nervous system.

→ The enteric nervous system stimulates and coordinates the breakdown of food, absorbing nutrients and expelling wastes from the body.

→ We secrete around 1 to 1.5 liters of saliva per day.

→ Oxidation of food is required to release energy.

→ Respiration is controlled by the medulla oblongata of the autonomous nervous system.

→ Digestion occurs in the food canal, coordination of respiration and blood circulation is necessary otherwise oxidation of food and transport of substances will not take place.

→ Ghrelin: It is a hormone produced mainly by the cells lining the human stomach and cells of the pancreas which stimulate hunger.

→ Leptin: It is the hormone that suppresses hunger.

→ Gustatory: Concerned with tasting or the sense of taste.

→ Chemoreceptors: Sensory cells or organs responsive to chemical stimuli.

→ Papillae: One of the certain small protuberances concerned with the senses of touch, taste, and smell.

→ Food Bolus: A small rounded mass of substance, especially of chewed food at the moment of swallowing.

→ Peristalsis: Contraction and relaxation of circular and longitudinal muscles in the esophagus bring a wave Like motion that propels the food bolus into the stomach by the action called peristalsis.

→ Chyme: The partly digested food in the stomach.

→ Pyloric Sphincter: Muscles present at the opening of the stomach and the first part of the small intestine and duodenum.

→ Villi: These are tiny finger-like projections that enable the small intestine to absorb nutrients from food.

→ Medulla oblongata: The continuation of the spinal cord within the skull, forming the lowest part of the brain stem and containing control centers for the heart and lungs.

→ Brain stem: The central trunk of the mammalian brain, consisting of the medulla oblongata, Ponsvaroll, and midbrain.

→ Hunger pangs: These are the contractions made by the stomach when we feel hungry.

→ Stale food: Food that is not freshly prepared but not harmful. It may not taste good.

→ Sipping: To drink a liquid by taking small mouthfuls.

→ Relish: Liking or enjoyment of the taste of something.

→ Palate: The roof of the mouth, separating the cavities of the mouth and nose invertebrates.

→ Munch: To chew with the steady or vigorous working of the jaws, often audibly.

→ MasticatIon: Biting and grinding food in our mouth so it becomes soft enough to swallow.

→ Belching: It is the emission of wind noisily from the stomach through the mouth.

→ PorrIdge: It is a dish made by boiling ground, crushed or chopped cereal In water, milk, or both.

→ Rumination: The process of rechewing the cud to further break down plant matter and stimulate digestion is called rumination.

→ Succus entericus: Intestinal juice secreted by glands lining the small intestinal walls. It continues downwards to form the spinal cord.

→ Neurotransmitter: A chemical substance that is released at the end of a nerve fiber by the arrival of a nerve impulse and by diffusing across the synapse and junction. It affects the transfer of the impulse to another nerve fiber, muscle fiber, or some other structure.

→ Second brain (or) Enteric nervous system: One of the main divisions of the autonomic nervous system and consists of a mesh-like system of neurons that governs the function of the gastrointestinal system.

→ Colon: It is the last part of the digestive system in most vertebrates. It removes water, salt, and some nutrients forming stool.

→ Anal sphincter: Either of two sphincters controlling the closing of the anus.

→ Ivan Petrovich Pavlov [1849 – 1936]:

• Ivan Petrovich Pavlov [1849 – 1936] was a famous Russian physiologist.
• He devoted his life to the study of physiology and sciences, making several remarkable discoveries and ideas that were passed on from generation to generation.
• Inspired when the progressive ideas which D.l. Pisarev, the most eminent of the Russian literary critics of the 1860s and I. M. Sechenov, the father of Russian physiology, were spreading, Pavlov abandoned his religious career and decided to devote his life to science.
• In 1870 he enrolled In the physics and mathematics faculty at the University of Saint Petersburg to take the course in natural science.
• He won the Nobel Prize for Physiology or Medicine in 1904.

Students can go through AP State Board 9th Class Physical Science Notes Chapter 8 Gravitation to understand and remember the concept easily.

AP State Board Syllabus 9th Class Physical Science Notes Chapter 8 Gravitation

→ Uniform circular motion is a motion of the body with a constant speed in a circular path

→ The acceleration which can change only the direction of the velocity of a body is called centripetal acceleration.

→ The net force which can change only the direction of the velocity of a body is called centripetal force directed towards the centre of the circle.

→ Centripetal force F_c = mv²/R

→ The universal law of gravitation states that everybody in the universe attracts other bodies within a force that is directly proportional to the product of their masses and inversely proportional to the square of the distance between them.

→ Universal gravitational constant G = 6.67 × 10^-11 Nm² kg^-2

→ Acceleration due to gravity (g) is independent of the mass of the body

→ When a body is thrown up ‘g’ is taken as negative and for a freely falling body, ‘g’ is positive.

→ A body is said to be free-falling when it starts with ‘zero’ velocity and travelling vertically downward.

→ During free-fall conditions, the body is in a state of weightlessness.

→ The point where total weight appears to act is called the ‘centre of gravity.

→ If we draw a line straight down from the centre of gravity of an object of any shape and it falls inside the base of the object, then the object will be stable

→ If the line through the centre of gravity falls outside the base then the object will be unstable.

→ The body is in equilibrium when the weight vector goes through the base of the body.

→ The distance of the moon from the centre of the earth is 384400 km (or) 3.844 × 10¹⁰ cm.

→ The time period of the moon around the earth = 27.3 days (or) 2.35 × 10⁶ s.

→ Acceleration of bodies acquired near the surface of earth ‘g’ = 981 cm/s² (or) 9.81 m/s²

→ Radius of earth Re = 6.4 × 10⁶ km.

→ Universal gravitational constant G = 6.67 × 10^-11 Nm² kg^-2.

→ Mass of the earth (M) = 6 × 10²⁴ kg.

→ Uniform circular motion: The motion of a body with constant speed in a circular path is called uniform circular motion.

→ Centripetal acceleration: The acceleration which causes changes only in the direction of the velocity of a body is called centripetal acceleration and it is always directed towards the centre of the circle.

→ Centripetal force: The net force required to keep a body in uniform circular motion is called centripetal force.
F = mv²/ R

→ Centre of gravity: The point where total weight appears to act is called the centre of gravity.

→ Law of gravitation: Every object in the universe attracts other bodies. The force of attraction between the bodies is directly proportional to the product of masses and inversely proportional to the square of the distance between them.

→ Weight: The weight of an object is the force of gravity acting on it.
W = mg

→ Weightlessness: During free-fall conditions, the body is in a state of ‘weight lessness’.

→ Stability: If we draw a line straight down from the centre of gravity of an object of any shape and it falls inside the base of the object, then the object will be stable.

→ Freefall: A body is said to be free-falling when it starts with ‘zero’ velocity and travelling vertically downward.

→ Sir Isaac Newton

• Newton was a British physician and mathematician.
• His lifetime is from 25-12-1642 to 20-03-1727.
• He studied the motion of bodies and framed the laws of motion.
• He is well known for his famous universal law of gravitation.

Students can go through AP State Board 10th Class Biology Notes Chapter 6 Reproduction to understand and remember the concept easily.

AP State Board Syllabus 10th Class Biology Notes Chapter 6 Reproduction

→ Reproduction is necessary for the perpetuation and continuation of life.

→ Reproduction is of mainly two types – sexual and asexual reproduction.

→ Asexual reproduction involves a single parent without the fusion of gametes.

→ The fusion of gametes takes place in sexual reproduction.

→ In sexual reproduction, only half of each parent’s chromosomes are passed to the next generation.

→ Fission, budding, fragmentation, regeneration, spore formation are the ways of asexual reproduction.

→ Vegetative propagation is of two types – natural and artificial propagation.

→ In natural vegetative propagation, new plants are produced from vegetative parts like leaves, stems and roots etc.

→ Artificial vegetative propagation is done through cutting, layering and grafting. Through grafting, we can acquire desirable characters of plants.

→ Tissue culture is a modern technique of growing plants in which more plants can be produced in a short time.

→ Fungi reproduce asexually through spore formation.

→ Sexual reproduction involves the fusion of male and female gametes. Union of gametes is known as fertilisation.

→ Fertilization takes place either outside the body of the mother or inside the mother’s body.

→ The male reproductive system consists of a pair of the testis, accessory glands and a system of ducts.

→ Testes are the male reproductive organ and produce spermatozoa or sperms and also secrete male sex hormone called testosterone.

→ Accessory glands include one prostrate and two Cowper glands which secrete a fluid called semen.

→ The duct system consists of Vasefferentia, epididymis, vas deference etc.

→ The sperm cell is a flagellated structure with a long tail that helps it to move towards the ovum.

→ The female reproductive system consists of a pair of ovaries that produce the ovum or egg

→ Graffin follicles of the ovary produce ova.

→ In human beings fertilisation occurs in the fallopian tube of the female reproductive system.

→ The placenta is a tissue formed by the cells from the embryo and the mother and it supplies nutrients to the embryo.

→ From the third month of pregnancy, the embryo is called a foetus.

→ Corian and Amnion are the membranes formed by the growing embryo.

→ The umbilical cord connects the embryo with the placenta.

→ The gestation period in human beings is 9 months or 280 days.

→ The reproductive part of the flower that contains sex cells or germ cells is stamens and carpels.

→ Pollen grains are spores produced by pollen mother cells present in the pollen sac of the anther.

→ Pollen grain germinates on stigma and produces a slender thin-walled pollen tube, one of its two nuclei divides and forms two sperms.

→ Union of one sperm with the egg in embryosac is called fertilization.

→ Union of second sperm with fusion nucleus is known as double fertilisation.

→ Continuation of life starts from cells either those of the general body or the sex cells.

→ Rudolph Virchow discovered cell division in 1855.

→ Robert Remak in 1852 published observations on cell division.

→ Walther Flemming in 1879 discovered chromosomes that appear double in nature.

→ Wilhelm Roux proposed that chromosomes carried a different set of heritable elements.

→ Gregor Mendel in 1866 published a paper on heritable elements in peas.

→ August Weiseman hypothesised that in successive generations, individuals of the same species have the same number of chromosomes.

→ The scheme of the mitotic division was confirmed in 1904 by Theodor Boveri.

→ The double helix structure of DNA was discovered by Watson and Crick in 1853.

→ The number of chromosomes in man is 46.

→ Cells divide for the growth of the individual to repair and replace the wear out cells and also for the formation of gametes.

→ Cell division is of two types

1. Mitosis or somatic cell division and
2. Meiosis or reproductive cell division.

→ Somatic cells from the body of the organism whereas germ cells participate in reproduction.

→ Interphase can be divided into three phases. They are the G₁ phase, S phase and G₂ phase.

→ Prophase, Metaphase, Anaphase and Telophase are the different stages in mitosis.

→ Meiosis has two phases, during the first phase the parent cell divides twice.

→ The second phase of meiosis is similar to normal mitosis.

→ The division of cytoplasm is Cytokinesis and the division of the nucleus is called Karyokinesis.

→ After mitosis two daughter cells are formed whereas after meiosis four daughter cells are formed.

→ Sexual maturation does not necessarily mean that the body or the mind is ready for sexual acts.

→ Sexual act transmits many diseases like Gonorrhoea, Syphilis and AIDS.

→ Andhra Pradesh has the highest number of HIV patients in the country.

→ Contraception to avoid pregnancy can be achieved by the use of condoms, oral pills, copper-T and surgical methods like Vasectomy and Tubectomy.

→ Teenage motherhood should be avoided.

→ Girls below 18 years of age should not be married.

→ The male and female child sex ratio is declining due to female foeticide.

→ Determination of sex before birth is illegal.

→ As a citizen of India, we should have knowledge of reproductive health not only to control high population growth but also to create a healthy society.

→ Progeny: A genetic descendant or offspring; The young of 1mai and plants.

→ Cyst: A small capsule-like sac that encloses certain organisms in their dormant or larval stage.

→ Fragmentation: Asexual reproductive method in multicellular organisms as in algae. Here the filaments break into parts and each part grows into a new individual.

→ Regeneration: It is the capacity to regenerate the full body from a part of the body of several organisms. eg: Hydra, Planaria.

→ Vegetative propagation: Production of new plants from the vegetative parts such as roots, stems and leaves.

→ Artificial propagation: The process of growing many plants from one plant by man-made methods.

→ Parthenogenesis: It is the process of development of an organism from an unfertilized egg. eg: Drones (Male honey bees).

→ Cutting: A vegetative propagation method in which a piece of stem or root of the source plant is placed in suitable soil to get a new plant.

→ Layering: A vegetative propagation method in which a portion of an aerial stem grows roots while still attached to the parent plant and then detaches as an independent plant.

→ Grafting: lI is a technique of inserting a part of one plant into another plant, that the two will unite and continue their growth.

→ Stock: The portion of the graft which is attached to the soil.

→ Scion: It is the upper part of the union in grafting which has lost its root system.

→ Desirable characters: The features of plants which we like to have in grafting.

→ Tissue culture: Technique used to maintain or grow cells, tissues or organs under sterile conditions on a nutrient culture medium of known composition.

→ Amniotic fluid: Protective fluid (liquid) contained by the amniotic sac of a pregnant female.

→ Placenta: it is the part that connects the developing foetus to the uterine wall to allow nutrient uptake, waste elimination and gas exchange via the mother’s blood supply.

→ Umbilical cord: It is a tube-like structure formed by the allantois membrane of the embryo. It connects the embryo with the placenta.

→ MitosIs: A cell division that occurs in somatic or vegetative cells forming two daughter cells having the same number of chromosomes as in their parental cell.

→ Meiosis: Cell division which occurs in germ cells or reproductive cells forming four daughter cells (gametes) having half of the number of chromosomes when compared to their parental cell.

→ Endometrium: The glandular mucous membrane lining the internal surface of the uterus in mammals.

→ Chromatid: One copy of a duplicated chromosome is generally joined to the other copy by a centromere, for the process of nuclear division.

→ Chromosome: A thread-like structure of nucleic acid (RNA, DNA) and proteins found in cells, carrying genetic information In the form of genes.

→ Foeticlde: It is the act of causing the death of a foetus by destruction or aborting.

→ HIV: Human Immuno Deficiency Virus: A virus that causes immunodeficiency in human beings.

→ AIDS: Acquired Immuno Deficiency Syndrome.

→ Vasctðrny: It Is a surgical procedure (or male sterilization In which a small portion of vas deferens is removed and cut ends are tied.

→ Tubedomy: A surgical procedure for female sterilization In which a small portion of the fallopian tube is removed and the cut ends are tied.

→ Budding: A bud develops as an outgrowth due to repeated cell division at the specific site which after developing into individuals detach from the body of the parent to become new individuals. eg: Hydra.

→ Binary fission: Asexual reproduction method in which an organism split Into two equal halves. Eg: Paramoecium, bacteria.

→ Sporophyll: Leaf that bears sporangia Is called the sporophyte. Eg: Ferns and mosses.

→ Sporangia: A structure within which spores are formed.

→ TestIs: Male reproductive organ which produces spermatozoa or male reproductive cells and male sex hormones.

→ Scrotum: A pouch of skin containing the testicles.

→ Seminiferous tubules: These are the sites In the testis where spermatozoa mature.

→ Vasa efferently: Any of a number of short ducts that carry sperm from the testis to the epididymis.

→ Epididymis: It Is a long, coiled tube that stores sperms and transports them from the testes.

→ Chorlton: It Is the outer membrane of the growing embryo.

→ Amnion: It is the sac-like structure around the embryo.

→ Anti-Retroviral Therapy (ART): It Is a treatment for AIDS disease. It Includes using multiple antiviral drugs in an attempt to control HIV infection.

→ Contraceptive: Any device or chemical which prevents pregnancy in a woman is called a contraceptive.

→ Epicotyl: It is the embryonic shoot above the cotyledons.

→ Hypocotyl: It is the base stem under the spent withered cotyledons.

→ Colostrum: The first secretion from the mammary glands after giving birth, rich in antibodies.

→ PEN: Primary Endospermic Nucleus.

→ Reproduction in animals:

→ Reproduction in plants:

→ Cell Division:

→ Cell Cycle:

→ Methods of Contraception:

→ Flower:

→ Dr. Potu Narasimha Rao:

• Dr Potu Narasimha Reo is a renowned scholar and an eminent cytologist who came from a poor family in Muppalla village of the Guntur district.
• He did his research on the cytogenetics of tobacco plant and cancer cells in a culture medium.
• He conducted researches in cell kinematics and triggering factor of cell division.
• He observed the interphase and its three phases.
• To understand the functional relationship between these phases, he did elegant experiments on cell fusion techniques along with his research associate Dr Johnson.
• His researches revealed that the cell cycle is sequential, unidirectional and controlled by a series of chemical signals.

Students can go through AP State Board 9th Class Physical Science Notes Chapter 7 Reflection of Light at Curved Surfaces to understand and remember the concept easily.

AP State Board Syllabus 9th Class Physical Science Notes Chapter 7 Reflection of Light at Curved Surfaces

→ The concave mirror converges the parallel light beam at one point. So it is called a converging mirror.

→ Convex mirror diverges the parallel light beam. So it is called a diverging mirror.

→ We always get a virtual and diminished image due to a convex mirror.

→ Mirror formula is \(\frac{1}{f}=\frac{1}{u}+\frac{1}{v}\)
f = focal length; u = object distance; v = image distance

→ Focal length is positive for a concave mirror and negative for a convex mirror.

→ The image distance is negative for a real image and positive for a virtual image.

→ The height of the object and height of the image is positive, if measured upward from the axis and negative if measured downwards.

→ Magnification is positive for erect images and negative for the inverted images.

→ Solar cooker works on the principle of converting sunlight at a point due to concave mirror.

→ Magnification: m = \(\frac{\text { size of the image }}{\text { size of the object }}\) (or) \(\frac{\mathrm{h}_{1}}{\mathrm{~h}_{\mathrm{o}}}\)
(OR)
m = – \(\frac{\text { image distance }}{\text { object distance }}=-\frac{v}{u}\)

→ We should use sign convention every time while using the formulae of the mirrors.

→ It is easy to understand the certain properties of light by drawing a ray diagram

→ Curved Surface: The surfaces which are not flat are called curved surface

→ The angle of incidence (∠i): The angle between the incident ray and normal is called the angle of incidence.

→ The angle of reflection (∠r): The angle between normal and reflected rays is called the angle of reflection.

→ Normal: The Pine perpendicular to the surface is called normal.

→ Centre of curvature (C): The normal from a concave mirror converges at a point that point is called the center of curvature.

→ The radius of curvature (R): The distance between vertex and center of curvature is called the radius of curvature.

→ Principal axis (or) Central axis: The horizontal line which passes through the center of curvature and pole.

→ Pole (P) (or) Vertex: The point where the central axis touches the mirror.

→ Focus or focal point (F): The rays coming from distinct objects parallel to the concave mirror will converge at a point called focus or focal point.

→ Focal length (f): The distance between vertex and focus.

→ Object distance (u): The distance between object and mirror is called object distance.

→ Image distance (v): The distance between image and mirror is called image distance.

→ Virtual image The Image formed in the mirror by extending the rays backward is called a virtual image.

→ Real image: The image formed due to the converging of light rays is a real image.

→ Ray diagram: A diagram showing the paths of selected rays through an optical system.

→ Magnification (m): Ratio of the size of the image to the size of the object.

→ Reflection: The bouncing back of the light is called reflection.

→ Incident ray: The ray which is an incident on a surface is called an Incident ray.

→ Reflected Ray: The ray which is reflected from the surface is called a reflected ray.

→ Virtual image: Virtual image ¡s the ¡mage formed due to diverging of light rays.
(OR)
The Image formed due to the extension of rays in the backward direction.

→ Spherical mirror: A mirror that has a curved reflective surface is a spherical mirror.

→ Concave mirror: A spherical mirror whose reflecting surface is curved inwards is called a concave mirror.

→ Convex mirror: A spherical mirror whose reflecting surface is curved outwards is called a convex mirror.

→ Pierre de Fermat:

• A French Lawyer at the Parliament of Toulouse, France, and an amateur mathematician.
• He made notable contributions to analytical geometry, probability, and optics.
• He proposed his principle on the light which states that light selects the path which takes the least time to travel. This principle was famous as the Fermat principle.

Students can go through AP State Board 9th Class Physical Science Notes Chapter 6 Chemical Reactions and Equations to understand and remember the concept easily.

AP State Board Syllabus 9th Class Physical Science Notes Chapter 6 Chemical Reactions and Equations

→ A chemical change is a permanent change.

→ In a chemical change, two substances react chemically to form new substances with different properties.

→ Chemical reactions are characterized by one or more of the following characteristics – the evolution of gas, change of color, formation of a precipitate, energy changes, and change of state.

→ A chemical equation represents a chemical reaction.

→ A complete chemical equation represents the reactants, products, and their physical state.

→ Reactions in which heat energy is absorbed by the reactants are endothermic reactions.

→ In exothermic reactions, heat energy is released by the reactants.

→ A chemical equation is balanced so that the number of atoms of each type involved in a chemical reaction is the same on the reactant and product sides of the equation.

→ Equations must always be balanced.

→ A combination reaction or synthesis is a reaction in which two or more substances combine to form a single substance.

→ A decomposition reaction is one in which a compound breaks up into two or more substances.

→ In a displacement reaction, one element replaces another element from a compound.

→ In a double decomposition reaction, two compounds react by exchanging their radicals.

→ Oxidation is a reaction involving the addition of oxygen or removal of hydrogen from a substance.

→ Reduction is a reaction involving the addition of hydrogen or the removal of oxygen from a substance.

→ Precipitation reactions produce insoluble salts.

→ According to the law of conservation of mass, “Mass can neither be created nor destroyed in a chemical reaction”.

→ The chemical equations are balanced to satisfy the law of conservation of mass in chemical reactions.

→ We should never change the formula of an element or a compound to balance an equation.

→ The process of making the number of different types of atoms equal on both sides of an equation is called the balancing of the equation.

→ All the combustion reactions are exothermic reactions.

→ The substance which gets oxidized is the reducing agent.

→ The substance which gets reduced is the oxidizing agent.

→ Two common effects of oxidation reactions that we observe in daily life are

1. Corrosion of metals
2. Rancidity of food

→ Corrosion causes damage to iron appliances.

→ When fats and oils are oxidized, they become rancid.

→ The precipitate is an insoluble substance.

→ Reactants: The substances which undergo chemical change in the reactions are called reactants.

→ Products: New substances formed in the reaction are called products.

→ Exothermic reaction: Reaction during which heat is released.

→ Endothermic reaction: Reaction in which heat is absorbed.

→ Chemical combination: It is a reaction in which two or more substances combine to form a single substance.

→ Chemical decomposition: It is a reaction in which a compound breaks up into two or more substances.

→ Displacement reaction: More active element replaces less active element from its compound in a chemical reaction.

→ Double displacement reaction: If two reactants exchange their constituents chemically and form two products, then the reaction is called a double displacement reaction.

→ Oxidation: It is a reaction involving the addition of oxygen or removal of hydrogen from a substance.

→ Reduction: It is a reaction involving the addition of hydrogen or removal of oxygen from a substance.

→ Corrosion: Chemical or electrochemical attack the surface of a metal.

→ Rancidity: The condition produced by aerial oxidation of fats and oils in foods marked by unpleasant smell and taste is called rancidity.

→ Antioxidants: Substances that prevent oxidation.

→ Chemical equation: A way of denoting a chemical reaction using the symbols for the participating particles (atoms, molecules, ions, etc.).

→ Chemical reaction: A change in which one or more chemical elements or compounds form new compounds.

→ Chemistry: The study of the elements and the compounds they form.

→ Oxidizing agents: Substances that oxidize other substances by providing oxygen to them or removing hydrogen from them.

→ Reducing agents: Substances that reduce other substances by removing oxygen from them or by supplying hydrogen to them.

→ Crystal: A solid in which atoms are arranged in a regular pattern.

→ Tarnish: To make something lose its shine and make it dull because of oxidation or rust.

→ Alloy: A material consisting of two or more metals or a metal and a non-metal. Ex: Steel.

→ Galvanizing: Iron or steel that has been coated with a layer of zinc to protect it from corrosion.

→ Rancid: Sour (or) Stale.

→ Redox reactions: The reactions in which both reduction and oxidation occur simultaneously are called redox reactions in short.

→ Exo: Outside.

→ Endo: Inside.

→ Thermo: Heat.

→ Respiration: When we inhale oxygen, it enters our body and combines with glucose in the cells of our body, and releases energy which helps to do the various works.

→ Henry Cavendish (1731 – 1810):

• Henry Cavendish conducted first his experiments on heat, electricity, and magnetism.
• He showed that water is composed of oxygen and hydrogen.
• He measured heats of fusion and evaporation as well as specific heats and those of the mixing of solutions in water.
• Cavendish’s measurements of the freezing points of various solutions showed the existence of compositions that yield maximum and minimum freezing points
• Cavendish’s experiments included the investigation of capacitance.
• In his experiments, he measured the strength of a current by shocking himself and estimating the magnitude of the pair.

Students can go through AP State Board 10th Class Biology Notes Chapter 5 Coordination to understand and remember the concept easily.

AP State Board Syllabus 10th Class Biology Notes Chapter 5 Coordination

→ Living organisms respond and react to their environment.

→ All our functions are carried out by an effort of several systems working together.

→ The nervous system and endocrine system are the two systems that control and coordinate various functions in the body.

→ The responses of the nervous system can be classified as a reflex, voluntary and involuntary actions.

→ Responses are brought about by rapid changes in some muscles.

→ The human nervous system is studied under two divisions. The central nervous system and the peripheral nervous system.

→ Galen concluded that nerves are of two kinds

1. Those of sensation and
2. Those of action.

→ The neuron is the structural and functional unit of the nervous system.

→ Each nerve cell consists of a cell body, dendrites, and axon.

→ Synapse is the functional region of contact between two neurons.

→ Basing on the pathways followed nerves are classified mainly into three different types.

→ Afferent or sensory nerves carry information from the sense organs to the central nervous system.

→ Efferent or motor nerves carry messages from the central nervous system to parts that or the effector organs.

→ Association neurons link afferent and efferent nerves.

→ Responses on which we may not have control are called reflexes.

→ The existence of the knee jerk was first noted in 1875.

→ The pathway of reflex action is called a reflex arc.

→ The central nervous system includes the brain and spinal cord.

→ The brain is the highest coordinating center in the body.

→ The brain is protected by the cranium.

→ The brain is covered by three membranes called meninges.

→ The space between the membrane is filled with cerebrospinal fluid.

→ The brain has three divisions:

1. Forebrain,
2. Midbrain and
3. Hindbrain.

→ The forebrain consists of the cerebrum, diencephalon.

→ Midbrain has optic lobes.

→ Hindbrain has cerebellum, medulla oblongata.

→ The brain weighs approximately 1400 gms.

→ The spinal cord is a cylindrical structure enclosed within the vertebral column.

→ There are 12 pairs of cranial nerves that arise from the brain and 31 pairs of spinal nerves.

→ The dorsal root carries messages of sensation inwards while the ventral root carries outwards the instruction for muscular contraction.

→ The peripheral nervous system is the network of spinal and cranial nerves that are linked to the brain and spinal cord.

→ Many activities of the internal organs like the heart, blood vessels, and glands are controlled by the autonomous nervous system.

→ Neurons present in our digestive tract is named as small brain and the system is called the enteric nervous system.

→ ‘sugar diabetes is a condition in which the amount of free sugar in the blood and urine is called of the pancreas.

→ The chemical substances produced by endocrine glands are known as hormones.

→ The feedback mechanism regulates the timing and amount of hormones released.

→ Plant hormones or growth substances coordinate the activities of the plant.

→ Major plant hormones are auxins, gibberellins, cytokinins, abscisic acid, and ethylene.

→ Auxins are responsible for cell elongation and differentiation of shoots and roots.

→ Gibberellins help in the germination of seeds and sprouting of buds; elongation of stems and breaking the dormancy in seeds and buds.

→ Abscisic acid helps in the closing stomata and seed dormancy.

→ Cytokinins promote cell division; the promotion of sprouting of lateral buds, delay the aging in leaves, the opening of stomata.

→ Ethylene is useful in ripening fruit.

→ Directional movements in plants in response to specific stimuli like light, chemicals, etc., are called tropic movements.

→ The bending of plants towards light is phototropism.

→ The downward movement of a plant in response to gravitational force is called geotropism.

→ The movement due to chemical stimulus is seen during the pollen tube growth is called chemotropism.

→ Response: Reaction, a reaction to something.

→ Stimuli:

• A thing or event that evokes a specific functional reaction in an organ or tissue.
• Something causing or regarded as causing a response.

→ Neuron: The structural and functional unit of the nervous system.

→ Schwann cell: A cell that forms spiral layers around a myelinated nerve fiber between two nodes of Ranvier and forms the myelin sheath consisting of the Inner spiral layers from which the protoplasm has been squeezed out.

→ Axon: The long projection from the cell body that extends to different parts of our body. The axon is to transmits information to different neurons, muscles, and glands.

→ Synapse: It ¡s the functional Junction between the two neurons through which information is transmitted or relayed to another neuron.

→ Afferent or Sensory nerves: Carry information from the receptor to the association neurons in the spinal cord.

→ Efferent or motor nerves: Carry information from the spinal cord or brain to the effector organs.

→ Association nerves: Process the information and generates responses.

→ Central nervous system: It includes the brain and spinal cord. It coordinates all neural functions.

→ Brain: An organ of soft nervous tissue contained in the skull of vertebrates. It coordinates the center of sensation and intellectual and nervous activity.

→ Spinal cord: Part of the central nervous system that acts as a relay station. It plays a major role in reflex actions.

→ Cerebrospinal fluid: Fluid present between the inner and middle layers. Protects the brain from mechanical shocks.

→ Peripheral nervous system: The nervous system outside the brain and spinal cord. Its main function is to connect the central nervous system to the limbs and organs.

→ Insulin: It Is the hormone produced by islets of Langerhans of the pancreas. It regulates sugar levels in the blood. Its deficiency results in diabetes mellitus.

→ Endocrine glands: These are also known as ductless glands. Their secretion is directly released into the blood (Hormone). They bring about chemical coordination in living organisms. e.g.: Pituitary, Thyroid, Parathyroid, Pancreas, and Adrenal gland.

→ Hormones: The secretion of endocrine glands is a hormone. Chemical coordination is brought out by hormones.

→ Feedback mechanism: It helps the organism to maintain homeostasis or dynamic equilibrium. Homeostasis is the maintenance of a stable internal state within an organism. It regulates the action of hormones.

→ Plant hormones: Coordinate the growth processes of the plant. e.g.:Auxins, Gibberellins, Cytokinins, Abscisic acid, and Ethylene.

→ Tropic movements: When the fixed part of a stationary plant moves in response to a stimulus the reaction is known as a tropic movement.

→ Nastic movement.s: These are non-directional movements or responses to stimuli. e.g.: Temperature, humidity, light, etc.

→ PhototropIsm: Bending of the plant towards the light is called phototropism.

→ Reflex arc: The path followed by a nerve impulse starting from the receptor and finally reaching the effector is called reflex arc; a Structural and functional unit that carries reflex action.

→ Stumble: MomentarIly lose one’s balance; almost fall.

→ MenInges: The three layers covering the brain.

→ Vasomotor: It refers to actions upon a blood vessel that alters its diameter.

→ Autonomous nervous system: Part of the peripheral nervous system that regulates the functions of our internal organs.

→ Enteric nervous system: Nervous system is present in the digestive system, independent of the central or peripheral nervous system.

→ Goosebumps: A roughness of the skin produced by the erection of its papillae especially from cold, fear, or a sudden feeling of excitement.

→ Stumps: The bottom part of a tree left projecting from the ground after most of the trunk has fallen or been cut down.

→ Geotropism: Plant responding positively for gravitational force; Root growing downwards.

→ Hydrotropism: Roots of a plant growing towards the water in the soil.

→ Thigmotroplsm: Tendrils of a plant growing towards support and wind around them.

→ Chemotropism: Response to chemicals is called chemotropism.

→ Voluntary actIon: It occurs without the conscious choice of an organism. If it occurs specifically in response to a stimulus, it will be known as a reflex.

→ Involuntary actIon: It occurs because of choice. It may or may not occur with the awareness of the organism performing it.

→ Lumbar region: It refers to the lower back, where the spine curves inwards towards the abdomen.

→ Aelius Galenus (Galen) – AD. 129-200:

• Galen was a prominent Greek-speaking Roman physician, surgeon end philosopher.
• Galen was the originator of the experimental method in medical investigation.
• He. proved that urine was formed in the kidney.
• His most important discovery was that arteries carry blood. He explained the differences between venous and arterial blood.
• Galen explained the difference between motor and sensory nerves.