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Here is a term paper on the ‘Nervous Coordination in Human Beings’ for class 9, 10, 11 and 12. Find paragraphs, long and short term papers on the ‘Nervous Coordination in Human Beings’ especially written for school and college students.
Nervous Coordination in Human Beings
Term Paper Contents:
- Term Paper on the Brain and Nervous System
- Term Paper on the Functions of the Major Parts of the Brain
- Term Paper on the Spinal Cord
- Term Paper on the Nerves
- Term Paper on the Reflex Action
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1. Term Paper on the Brain and Nervous System:
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The various organs of the body must work in coordination if an organism is to survive effectively in its environment. To achieve this, the body has a series of receptors which pass information about the environment to a coordinating centre called the central nervous system or CNS. The CNS is made up of the brain and the spinal cord. After receiving the information, the CNS directs a response in the appropriate effectors (muscles or glands).
The nervous system is made up of the central nervous system, or CNS (made up of the brain and spinal cord), and a system of nerves. Nerves carry impulses between receptor organs (e.g. the eyes), the CNS, and effectors (muscles or glands).
The most highly developed part of the CNS is the brain.
2. Term Paper on the Functions of the Major Parts of the Brain:
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a. Cerebrum:
The cerebrum is in the form of two matching halves – known as the cerebral hemispheres and is responsible for:
(i) The coordination of the organs of the body
(ii) The control of voluntary actions
(iii) The reception of sensation.
At the very front of the cerebrum is cerebrum the region responsible for memory and morals (the ‘higher mental activities’). At the back lies the region responsible for sight.
b. Cerebellum:
The cerebellum is the region of balance and instinct.
c. Medulla:
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The medulla joins the brain to the spinal cord. It controls unconscious activities such as heartbeat, peristalsis and breathing.
d. Hypothalamus:
The hypothalamus lies under the cerebrum and is the part of the brain responsible for monitoring changes, particularly in the blood. It may be regarded as the ‘homeostat’ of the body.
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e. Pituitary Gland:
Situated beneath the hypothalamus, the pituitary gland is made up partly of nerve tissue. It is sometimes called the ‘master’ gland because it manufactures chemicals called hormones and releases them into the blood. These hormones control the activity of many glands and other organs throughout the body, such as those responsible for growth (e.g. of bones) and development (e.g. sexual development). Therefore, the pituitary gland has a very important part to play in coordination. It is regularly ‘instructed’ by the hypothalamus.
3. Term Paper on the Spinal Cord:
In the same way that a series of nerves (cranial nerves) serve the brain, impulses are relayed to, and conducted from the spinal cord by nerves called spinal nerves. Spinal nerves are connected with receptors and effectors in parts of the body other than the head.
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In emergency situations, the spinal cord can receive and transmit impulses to bring about rapid, often protective responses called reflex actions. The central region of the spinal cord (the grey matter) contains nerve cells (relay neurones) involved solely in this process. The outer region of the spinal cord (the white matter) contains nerve cells involved in either supplying sensory information to the brain, or passing impulses on to muscles which are instructed by the brain (i.e. voluntary actions).
4. Term Paper on the Nerves:
A nerve is like a telephone cable- it contains a large number of small ‘wires’ called neurones. Each neurone is an individual nerve cell with its own cytoplasm, cell membrane and nucleus.
Neurones which conduct impulses from sensory receptors to the brain or spinal cord are called sensory neurones.
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Neurones which then direct those impulses either to other parts of the brain or to other parts of the spinal cord are called relay neurones.
Neurones which conduct impulses from the brain or spinal cord to effectors are called motor (or efferent) neurones.
Neurones are insulated by a fatty (‘myelin’) sheath. They are long, they target the exact area to be affected and they conduct their impulses very quickly. These features are vital if an action is to be taken very quickly to prevent damage, as in a reflex action.
5. Term Paper on the Reflex Action:
Definition of Reflex Action:
A reflex action is a coordinated response to a specific stimulus.
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In the example of the iris reflex, the brain is the part of the CNS involved, and the reflex action is called a cranial reflex.
When the spinal cord alone directs the response, the action is described as a spinal reflex. For example, when we quickly remove our finger from a hot object.
The sequence of events in a spinal reflex is:
1. A stimulus is received by the sensory receptor (in the example given above, the hot object provides the stimulus and the sensory receptor is located in the finger).
2. An impulse is generated and carried along by sensory neurones towards the spinal cord.
3. The sensory neurones become part of a spinal nerve.
4. The impulse travels toward the spinal cord along the dorsal root. The dorsal root is part of the linking pathway between outside stimuli and the spinal nerve.
5. Impulses arrive at the nerve endings of the sensory neurone in the grey matter of the spinal cord.
6. The nerve endings release a chemical which diffuses across a gap – the synapse – between the sensory neurone and the nerve endings of a relay neurone. The chemical stimulates the relay neurone to produce an impulse.
7. Another synapse links the relay neurone with a motor neurone.
8. The impulse travels along motor neurones away from the spinal cord along the ventral root. The ventral root is part of the linking pathway between the spinal nerve and the effector.
9. The nerve endings of the motor neurone are applied to the effector (the biceps muscle in this case).
10. A response is produced (as the biceps muscle contracts to lift the hand clear of the stimulus).
