Question

Distinguish between the following pairs of words:

(i) Nerve cell and neuroglia cell
(ii) Nervous system and hormonal system
(iii) Cranial nerve and spinal nerve
(iv) Cerebrum and cerebellum
(v) Adrenalin and acetylcholine
(vi) Motor and sensory nerve
(vii) Grey matter and white matter
(viii) Myopia and hypermetropia

Answer 1

(i)

Nerve cells	Neuroglial cells
They are the structural and functional units of nervous tissue.	They are the supporting cells of nervous tissue.
They are responsible for transmission of nerve impulses.	They form the packaging media between the nerve cells in the brain and the spinal cord. They provide nutrition to neurons.

(ii)

Nervous system	Hormonal system
The nervous system involves electrical impulses called nerve impulses.	The hormonal system involves hormones that are chemical substances.
Nerve impulses are conducted along nerve fibres.	Hormones are carried in the blood.
It is quick in response.	It is usually slow in response.
The duration of response is short.	The duration of response is long.

(iii)

Cranial nerves	Spinal nerves
Cranial nerves arise from the brain.	Spinal nerves arise from the spinal cord.
There are 12 pairs of cranial nerves.	There are 31 pairs of spinal nerves.

(iv)

Cerebrum	Cerebellum
It is the part of the forebrain that controls voluntary functions. It is the place where intelligence, willpower, etc., reside.	It is the part of the hindbrain that controls voluntary functions and helps maintain balance of the body (Muscular equilibrium).

(v)

Adrenaline	Acetylcholine
Adrenaline is a hormone produced by the adrenal glands during high stress conditions.	Acetylcholine is a key chemical in neurons that transmits information across the synaptic cleft.
It works by stimulating the heart rate, contracting blood vessels and dilating air passages, all of which work to increase blood flow to the muscles and oxygen supply to the lungs.	It functions in both the peripheral nervous system and the central nervous system. In the peripheral nervous system, this neurotransmitter is a primary component of the autonomic nervous system and works to activate muscles. In the central nervous system, it acts as part of a neurotransmitter system and plays a role in attention and arousal.

(vi)

Sensory nerves	Motor nerves
They are also known as afferent nerves.	They are also known as efferent nerves.
Receptor neurons carry nerve impulses from receptors or sense organs to the central nervous system.	They carry signals from the central nervous system to the effectors, such as muscles and glands.

(vii)

White matter	Grey matter
White matter is one of the two components of the central nervous system and consists mostly of myelinated axons.	Grey matter is a major component of the central nervous system, consisting of neuronal cell bodies, glial cells (astroglia and oligodendrocytes) and capillaries.
White matter appears white owing to the presence of large amounts of myelin, a fatty protein that serves as an insulator that helps in signal transmission.	Grey matter appears grey-brown owing to the presence of neuronal cell bodies and capillaries, as well as the relative lack of myelin.
A nerve impulse travels faster in white matter owing to the presence of a myelin sheath in the neurons present here.	A nerve impulse travels slowly in grey matter owing to the lack of myelinated neurons in it.

(viii)

Myopia	Hypermetropia
In myopia, the image of a distant object is formed in front of the retina.	In hypermetropia, the image is produced beyond the retina.
It can be produced by an abnormally long eyeball and abnormally high convexity of lens.	It can be produced by an abnormally short eyeball and low convexity of lens.
It can be corrected by using spectacles with suitable biconcave lens.	It can be corrected by using spectacles with suitable biconvex lens.