Question

In the brain of rabbit, aqueduct of sylvius is located in –
A) Diencephalon
B) Cerebellum
C) Hypothalamus
D) Midbrain

Answer 1

Hint: Aqueduct of sylvius – It is located in the midbrain part.
Brain is an important part of the nervous system. The brain is mainly divided into three parts – fore brain, midbrain and hindbrain.

Complete Answer:
A) Diencephalon – The fore-brain is also called prosencephalon, it is divided into two parts i.e. telencephalon and diencephalon. It is an unpaired part of the fore-brain. It is anteriorly covered by posterior ends of cerebral hemispheres. The dorsal wall contains a pineal stalk and anterior choroid plexus.
– Pineal stalk contains pineal gland.
– Ventral wall of the diencephalon is called hypothalamus. Ventral wall contains another stalk, called infundibulum, which contains pituitary gland.
– Diencephalon is also hollow, the cavity is called third ventricle or diocoel.

B) Cerebellum – It is a part of the hindbrain. Hind-brain has two parts – Cerebellum and Medulla oblongata.
– Cerebellum is the unpaired part. It is commonly called small brain.
– It serves for coordinating muscular actions and maintains balance during movement.

C) Hypothalamus – It is a part of the fore-brain. The ventral wall of diencephalon is called hypothalamus. It contains thirst and hunger centres.

D) Mid brain – It is also called mesencephalon. It has four optic lobes called corpora quadrigemina. The optic lobes are hollow. The cavities are called optocoels. These open into iter or aqueduct sylvius.
 – Optic lobes are concerned with sense of sight. They also control movement of eye muscles.

The correct option is D-Mid brain.

Note: Corpora quadrigemina acts as centres for auditory and visual reflexes and also connects forebrain and hindbrain.