Involuntary actions like blood pressure, salivation and vomiting are controlled by the _____.
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Medulla
The medulla (medulla oblongata) is the lowest part of the hindbrain, joining the brain to the spinal cord. It controls involuntary actions such as blood pressure, heartbeat, breathing, salivation, swallowing and vomiting.
Why the other options are incorrect
Option (1) Cerebrum — Incorrect. The largest part of the brain, the seat of voluntary actions, thinking and memory.
Option (2) Cranium — Incorrect. The bony case of the skull that protects the brain; it controls nothing.
Option (3) Spinal Cord — Incorrect. It carries messages between the brain and the body and controls spinal reflexes such as pulling the hand away from a hot object.