Neural control and coordination practice · Easy

Option A (10 pairs) is correct because frogs have 10 pairs of cranial nerves.

Option A (If both the assertion and the reason are true and the reason is a correct explanation of the assertion) is correct because in myelinated nerve fibers, the impulse jumps from one node of Ranvier to another due to ion exchange occurring only at the nodes.

Option D (Both (a) and (c)) is correct because the fight and flight response is mediated by the sympathetic nervous system.

Option C (Hydra) is correct because Hydra possesses a nerve net, a simple nervous system without a centralized brain.

Option A (If both the assertion and the reason are true and the reason is a correct explanation of the assertion) is correct because Vitamin A deficiency does cause night blindness, and this is because Vitamin A is a precursor to retinal, a component of visual pigments.

Option C (Blind spot) is correct because the blind spot is the area where the optic nerve leaves the eye, and therefore has no photoreceptor cells.