Question

question 21
1 pts
which part of the brain releases the hormone melatonin?
hypothalamus
thalamus
pineal gland
cerebellum
question 22
1 pts
the innermost layer of the meninges is the:
pia mater.
arachnoid membrane.
dura mater.
none of the above is correct.
question 23
1 pts
all of the following are characteristics of sympathetic preganglionic neurons except:
they secrete acetylcholine.,
they have long fibers from cns to ganglion.
dendrites and cell bodies are found in the lateral gray columns of thoracic and the first four lumbar segments of the spinal cord.
all of the above are correct.

Explanation:

• Question 21: The pineal gland is responsible for secreting melatonin, which regulates sleep - wake cycles. The hypothalamus is involved in many regulatory functions like body temperature and hunger, the thalamus relays sensory and motor signals, and the cerebellum is mainly for motor control.
• Question 22: The meninges have three layers. The innermost layer is the pia mater. The arachnoid membrane is the middle layer, and the dura mater is the outermost layer.
• Question 23: Sympathetic preganglionic neurons secrete acetylcholine. Their cell bodies are in the lateral gray columns of the thoracic and first four lumbar segments of the spinal cord. However, sympathetic preganglionic neurons have short fibers from the CNS (central nervous system) to the ganglion, while parasympathetic preganglionic neurons have long fibers from the CNS to the ganglion.

Answer:

Question 21: Pineal gland
Question 22: pia mater
Question 23: they have long fibers from CNS to ganglion