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
- Those of sensation and
- 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:
- Forebrain,
- Midbrain and
- 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.