Question

The third ventricle of the brain is situated in the
A. Base of telencephalon
B. Roof of metencephalon
C. Roof of diencephalon
D. Base of myelencephalon

Answer 1

Hint: The brain is a complex structure in the human. The brain works along with the nervous system and spinal cord. The brain consists of the three parts which are cerebrum, brainstem and cerebellum. The ventricular system is situated within the cerebrum. It consists of four interconnected ventricles and in them the cerebrospinal fluid is produced and circulated.

Complete answer:
The ventricles of the brain are the structures that give rise to the cerebrospinal fluid and transportation takes place around the cranial cavity. The ventricles are lined by the ependymal cells and form the choroid plexus. The choroid plexus is produced by the cerebrospinal fluid. There are four types of ventricles which are the right and left lateral ventricles, third ventricle and fourth ventricle.
The third ventricle is the connected ventricles of the ventricular system. It is a slit-like cavity that is formed in the roof of the diencephalon present between the two thalami. It is filled with cerebrospinal fluid. The third ventricle is connected at the superior anterior corner to the lateral ventricles through the interventricular foramen. At this corner, a third ventricle forms a bulb which is known as the anterior recess. The roof of the ventricles consists of choroid plexus and forms the inferior central portion of teal choroidea.
-The telencephalon is known as cerebrum and contains the cerebral cortex. The telencephalon is divided into dorsal telencephalon or pallium and it develops into cerebral cortex and ventral telencephalon or sub pallium and forms the basal ganglia.
-Metencephalon is the part of the hindbrain which differentiates into the pons and cerebellum. It contains a part of the fourth ventricle and nerves such as trigeminal nerve, abducens nerve, facial nerve and part of vestibulocochlear nerve.
-Myelencephalon forms the posterior part of the brain stem. It consists of medulla oblongata and forms the metencephalon and it connects to the spinal cord.

Hence, the correct answer is option (C).

Note: The ventricular systems consist of four different ventricles such as right ventricle, lateral ventricle, third and fourth ventricle. The third ventricle is situated at the roof of the diencephalon. The ventricle is lined by the ependymal cells and it produces the cerebrospinal fluid.