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Why This Chapter Is Free Marks
Every general science paper carries one or two nervous system questions, and they are almost never conceptual. They ask *which part does what*. Learn the division of labour once and you answer in five seconds.
The human nervous system splits into two halves:
> Central Nervous System (CNS) = brain + spinal cord — the decision makers.
> Peripheral Nervous System (PNS) = 12 pairs of cranial nerves + 31 pairs of spinal nerves — the wiring.
The PNS further splits into the somatic system (voluntary — you decide to lift your hand) and the autonomic system (involuntary — your heartbeat, digestion, sweating).
The autonomic system itself has two opposing branches: the sympathetic (fight or flight — pupils widen, heart races) and the parasympathetic (rest and digest — heart slows, digestion resumes). Papers love asking which branch does which, so fix that pair now.
1. Which part of the human brain controls balance, posture and coordination of body movement?
2. A person touches a hot vessel and instantly withdraws the hand. This reflex action is controlled by:
3. Which of the following is the longest cell in the human body?
4. How many pairs of spinal nerves arise from the human spinal cord?
5. Involuntary actions such as heartbeat, breathing and blood pressure are controlled by which part of the brain?
6. The junction or narrow gap across which a nerve impulse passes from one neuron to the next is called:
7. Body temperature, hunger, thirst and the sleep cycle are regulated by:
8. Which is the longest nerve in the human body?