AP Board 10th Class Biology Notes Chapter 1 Nutrition

Students can go through AP State Board 10th Class Biology Notes Chapter 1 Nutrition to understand and remember the concept easily.

AP State Board Syllabus 10th Class Biology Notes Chapter 1 Nutrition

→ In autotrophic nutrition, organisms are capable of producing complex carbohydrates, proteins, lipids, etc., from carbon dioxide and water using light as a source of energy.

→ Plants prepare their own food materials through a process known as photosynthesis.

→ C.B. Van Neil in 1931 proposed the following equation for photosynthesis
AP Board 10th Class Biology Notes Chapter 1 Nutrition 1

→ Van Neil first worked on purple sulphur bacteria and found light plays a specific role in photosynthesis.

→ Robert Hill showed 02 is released from water in photosynthesis.

→ The modified and balanced equation for photosynthesis is
AP Board 10th Class Biology Notes Chapter 1 Nutrition 2

→ If we boil a leaf in methylated spirit over a water bath it loses its chlorophyll.

→ Von Helmont found that water was essential for the increase of plant mass.

→ Oxygen was discovered by Priestly in 1774 the name oxygen was coined by Lavoisier in the year 1775.

→ Priestly hypothesized that plants restore air what breathing animals and burning candles remove.

→ Jan Ingenhousz experimentally proved that the hydrilla plant releases oxygen in bright sunlight.

→ Engelman detected the point of the maximum rate of photosynthesis.

→ Ingenhousz concluded that only green plant parts could carry out the process of photosynthesis.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ In 1817 Pelletier and Caventou extracted the green coloured substance from the leaf and named its chlorophyll.

→ Pigments other than green colour could also aid in the process of photosynthesis by passing on the energy of sunlight trapped by them to chlorophyll.

→ In 1883 Julius Von Sachs observed the presence of chlorophyll in organelles called chloroplasts.

→ In 1954 Daniel I.Arnon isolated chloroplasts from plant cells that carry photosynthesis.

→ The third layer of chloroplast around it forms a stacked sac-like structure called a granum.

→ Granum is the site for trapping solar energy. Light reactions occur in Granum.

→ The fluid-filled portion of the chloroplast is the stroma in which dark reactions occur.

→ The sunlight absorbing substances found in chloroplast are photosynthetic pigments.

→ Photosynthetic pigment chlorophyll contains one atom of magnesium.

→ Chlorophyll ‘a’ is blue-green in colour and chlorophyll ‘b’ is yellow-green colour.

→ The events that occur in chloroplasts during photosynthesis are

  • Conversion of light energy to chemical energy.
  • Splitting of the water molecule and
  • Reduction of carbon dioxide to carbohydrates.

→ The light reaction takes place in chlorophyll-containing thylakoids called grana of chloroplasts.

→ Photon is the smallest unit of light energy.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ The splitting of water molecules by light is known as the photolysis of water. Water splits into hydrogen (H+) and hydroxyl ion (OH).

→ Photolysis of water was discovered by Robert Hill. Hence it is known as Hill’s reaction.

→ The hydroxyl ions (OH) through a series of steps produce water (H2O) and oxygen (O2).

→ O2, ATP and NADPH are formed at the end of the light reaction.

→ The time gap between the light and dark reaction is less than even one-thousandth of a second.

→ The dark reaction does not depend on light.

→ In the dark reaction, the hydrogen of the NADPH is used to combine with CO2 by utilizing ATP energy and to produce glucose.

→ Heterotrophic nutrition involves the intake of complex materials prepared by other organisms.

→ Saprophytes like bread moulds, yeast, mushrooms, etc., break down the food materials outside the body and then absorb them.

→ Some organisms take in whole material and break it down inside their bodies, eg: animals.

→ Some organisms derive nutrition from plants or animals without killing them, eg: Cuscuta, lice, leeches and tapeworms.

→ Amoeba takes food through the projections of the body surface called pseudopodia.

→ In paramoecium, food is moved to a specific spot by the movement of cilia.

→ The parasitic plant Cuscuta (Dodder) absorbs food through haustoria from the body of the host.

→ The process of breaking down complex substances into simple substances with the help of enzymes is called digestion.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ The saliva secreted by three pairs of salivary glands contains an enzyme amylase (ptyalin). It helps in the breakdown of complex carbohydrates into simple ones.

→ The alimentary canal is a long tube extending from the mouth to the anus.

→ The parts of the human digestive system are the mouth, buccal cavity, pharynx, oesophagus, stomach, small intestine, large intestine, rectum and anus.

→ The food from the mouth to the stomach passes through the oesophagus by wave-like movements called peristaltic movements.

→ Food gets churned with gastric juice and HCl in the stomach.

→ Chyme is the partially broken food in the stomach which is in the form of a soft slimy substance.

→ The pyloric sphincter present at the end of the stomach releases small amounts of chyme into the small intestine.

→ The small intestine is the longest part of the alimentary canal.

→ Bile juice from the liver and pancreatic juice from the pancreas releases into the small intestine.

→ Bile juice helps in converting fats into small globule like forms by a process called emulsification.

→ Pancreatic juice contains trypsin and lipase for digesting proteins and fats respectively.

→ Taking food into the body is called ingestion.

→ Transport of the products of digestion from the intestine into the blood is called absorption.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ Maximum absorption of food takes place by finger-like projections called villi in the small intestine.

→ The passage of undigested material from the body by the way of the anus is called defecation.

→ Vomiting is the body’s method of throwing out unwanted or harmful substances from the stomach.

→ Reverse peristaltic movements occur in the stomach and oesophagus during vomiting.

→ Indigestion is caused by stomach and duodenal ulcers.

→ Intake of fibre rich food avoids constipation.

→ Our diet should be a balanced diet that contains proper amounts of carbohydrates, proteins, vitamins, mineral salts and fats.

→ Eating food that does not have one or more than one nutrient in the required amount is known as malnutrition.

→ Malnutrition is of three types

  1. Calorie malnutrition
  2. Protein malnutrition and
  3. Protein calorie malnutrition.

→ Kwashiorkor disease occurs due to protein deficiency.

→ Marasmus is a disease due to a deficiency of both proteins and calories.

→ Obesity occurs due to overeating and excess energy intake.

→ Vitamins are micronutrients required in small quantities. They are water-soluble (B complex, Vitamin C) and fat-soluble (Vitamin A, D, E and K). Eg: Animals,

→ Glucose: Simple carbohydrates formed at the end of the dark reaction in photosynthesis. It is oxidised to produce energy during respiration.

→ Starch: Et is a polysaccharide that is present only in plants. It forms the bulk of our food. Starches are extracted commercially from wheat, potatoes, rice, etc.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ Cellulose: Cellulose is a polysaccharide, that helps in forming the cell wall of plants, algae, fungi. It is digested by animals but not by human beings. It helps in the smooth movement of food in the alimentary canal.

→ Chloroplast: It is a plastid present only in the plant cells containing chlorophyll and pigments.

→ Grana: These are the stacked sac-like structures formed by the third membrane of the chloroplast. Light reaction of photosynthesis takes place in it.

→ Stroma: The zone between the Intergranum lamellae of a chloroplast filled with fluid. The dark reaction of photosynthesis occurs in the stroma.

→ Light reaction: Reaction of photosynthesis that occurs in the presence of light in the grana of the chloroplast.

→ Dark reaction: Reaction that takes place in absence of light or light-independent reaction. They occur in the stroma of the chloroplast.

→ Heterotrophic nutrition: It is a type of nutrition in which an organism cannot make its own food from simple inorganic materials like CO2, water and depends on other organisms for its food.

→ Parasitic nutrition: It is a type of heterotrophic nutrition ¡n which organisms derive their food from the body of other living organisms without killing them.

→ Haustoria: A specialized branch of the organ of a parasite, which penetrates the host tissue and absorbs nutrients and water.

→ Alimentary canal: It is the part of the digestive system which is like a long tube extending from mouth to anus.

→ Salivary glands: Glands that secrete saliva are called salivary glands. These are three pairs. Two pairs are located at the side of the jaw and below the tongue and one pair is located in the palate.

→ Peristaltic movements: The wave-like movements produced by the contraction and relaxation of the muscles present in the food pipe.

→ Amylase: An enzyme that hydrolyzes starch or glycogen to sugars.

→ Palm: The other name for salivary amylase.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ Penh: It is an enzyme produced by gastric glands in the stomach that helps to digest proteins in the food.

→ Chyme: It is the partially digested food in the stomach. Proteins and carbohydrates are broken down to some extent.

→ Sphincter: Ring like muscles present at the end of the stomach and allows a small amount of food into the small intestine.

→ Digestion: The process of breaking down complex substañces into simple substances SO2 that can be used by the body with the help of enzymes is called digestion.

→ Pancreas: It is a mixed gland. It secretes pancreatic juice which contains enzymes like trypsin and amylase. This gland lies between the spleen and duodenum.

→ Enzymes: These are a group of chemical substances which cause biochemical reactions. Helps in the conversion of complex food materials into simple substances.

→ Villi: These are finger-like projections formed from the intestinal wall. The digested food material ¡s absorbed by villi. They increase the area of absorption.

→ Bile Juice: Digestive juice secreted by the liver. Enzymes are absent in it. It helps in the breakdown of fat molecules by a process called emulsification.

→ Lipase: An enzyme that converts fats to fatty acids and glycerol. It is present in the pancreatic juice.

→ Fat: It is made up of fatty acids and glycerol. It will be used for the production of energy.

→ Liver: The largest gland in the body. It produces bile juice.

→ Emulsification: Conversion of fats into small globule like forms with the help of the bile juice is called emulsification.

→ Kwashiorkor: It ¡s a disease due to protein deficiency.

→ Marasmus: This is a disease due to a deficiency of both proteins and calories.

→ Apparent: Easily noticed or understood.

→ Nutrition: It is the procurement or intake of nutrients.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ Saprophytes: Organisms that obtain food from dead and decaying plants and animal bodies. e.g.: Bacteria and fungi.

→ Carbohydrates: These are energy-rich complex organic materials formed with carbon, hydrogen and oxygen. They are also called sugars.

→ Proteins: These are made up of amino acids which are used for growth and development.

→ Extinguish: To make a fire or light stop burning or shining.

→ Suffocate: To die or make someone die by preventing them from breathing.

→ Hypothesis: An idea that is suggested as a possible way of explaining a situation when you do not definitely know about it.

→ Pellets: A small ball of any soft substance.

→ Ingenious: It is the result of clever thinking and new ideas and works well.

→ Incense stick: A substance that produces a pleasant smell when you burn it.

→ Succession: A number of people or things that follow each other in time or order.

→ Access: A way of entering or reaching a place.

→ Strategy: A plan that is intended to achieve a particular purpose.

→ Lice: A small insect that lives on the bodies of humans and animals.

→ Ingest: Taking food into our body usually by swallowing.

→ Root rot: Decay or decomposition of the root.

→ Tangle: A twisted mass of thread, hair, etc., that cannot be easily separated.

→ Mastication: Chewing food or biting food into small pieces in our mouth.

→ Churn: Tostir,beat,mix.

→ Defecation: it is sending out solid waste food from our body through our bowels.

→ Roughages: These are fibres of either carbohydrates or proteins. They keep a person healthy by keeping the bowels working and moving other food quickly through the body.

AP Board Solutions AP Board 10th Class Biology Notes Chapter 1 Nutrition

→ Riddle: A question that is difficult to understand and that has a surprising answer.

→ Bilious: Feeling as if we might vomit, creating an unpleasant effect.

→ Seldom: Rarely, not often.

→ Constipation: The condition of being unable to get rid of waste materials from bowels easily.

→ Obesity: This condition occurs due to overeating and excess energy intake.
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→ C.B. Van Neil (1897 – 1985):

  • C. B. Van Neil was a Dutch American microbiologist.
  • He made key discoveries explaining the chemistry of photosynthesis.
  • By studying purple sulphur bacteria and green bacteria, he was the first scientist to demonstrate that photosynthesis is a light-dependent redox reaction, in which hydrogen from an oxidizable compound reduces carbon dioxide to cellular materials.
  • His discovery predicted that H2O is the hydrogen donor in green plants photosynthesis and is oxidised to