(a) Differences between Afferent neuron and Efferent neuron.
| Afferent neuron | Efferent neuron |
| It conducts impulses from peripheral receptors and tissue to central nervous system | It conducts impulses from central nervous system to effectors |
| It provides stimulus and evokes sense. | It results in the response by the effectors (muscles and glands) |
| They are sensory in nature. | They are motor in nature. |
(b) Conduction of nerve impulse in myelinated and non- myelinated nerve fibre.
| Conduction of nerve impulse in myelinated nerve fibre. | Conduction of nerve impulse in on- myelinated nerve fibre |
| Complete electrical insulation is provided to axon. | No perfect insulation. |
| Flow of ions associated with passage of nerve impulse is restricted to nodes of Ranvier and only small amount of ions pass. | Flow of ions occurs all along the fibre and large amount of ions pass along its length. |
| Impulse is conducted by saltatory conduction. | Impulse is conducted by steadily progressing ionic charge along the length. |
| Velocity of conduction increases. | Velocity of conduction is slow. |
| Less amount of energy is required. | More amount of energy is required. |
(c) Differences between vitreous humor and aqueous humor.
| Vitreous humor | Aqueous humor |
| It is thick jelly- like fluid present between retina and lens. | It is watery fluid present between lens and cornea. |
| It is of permanent nature and not replaced. | It is continuously secreted and drained out of eyes. |
| It does not have nutritive value. | It provides nourishment to lens, cornea and other parts of anterior chamber. |
(d) Difference between yellow spot and blind spot
| Yellow spot | Blind spot |
| 1. It has only cone cells and sharp image is formed at this spot. | 1. It has neither cone nor rod cells and no image is formed. |
Difference between cranial nerves and spinal nerves.
| Cranial Nerves | Spinal Nerves |
| They originate from the brain. | They originate from the spinal cord. |
| They may be sensory, motor or mixed. | They are all mixed in nature. |