Question

Pallium is
A. Lateral walls of diencephalon
B. Lateral walls of cerebrum
C. Floor of paracoel
D. Roof of paracoel

Answer 1

Hint: The brain is one of the largest and most important and complex structures. It performs several vital functions such as processing of information, nervous and motor responses etc. The brain is divided into three important parts which are the cerebrum, the cerebellum and the brain stem.

Complete answer:
The brain and the spinal cord form the central nervous system. During the process of development in living organisms, the brain can be divided into three parts. The three parts are the forebrain or the prosencephalon, midbrain or the mesencephalon and the hindbrain or the rhombencephalon. Each part of the brain gives rise to different parts such as the cerebrum, cerebellum and the brain stem.

The cerebrum is the most developed portion of the brain and consists of the major lobes. It is also known as the telencephalon. It consists of the cerebral cortex and other areas such as the basal ganglia, hippocampus and olfactory lobes. It is situated close to the cerebellum. The cerebrum develops from the prosencephalon. The cerebellum is the part of the hindbrain and is situated near the brain stem.

On the dorsal part of the cerebral hemisphere, the grey matter develops into a thicker layer and it is known as the pallium. The pallium covers the roof of the paracoel. The paracoel is also known as the lateral ventricles. The pallium is the region of the telencephalon and in mammals, it develops into the cerebral cortex. It forms the roof of the second cavity or the ventricle and is found in the cerebral cortex. The paracoel is also known as the second ventricle. The medial part of the pallium forms the hippocampus. The lateral and ventral pallium forms the olfactory cortex, bulbs and the pallial part of the amygdala.

The pallium receives the primary sensory afferent from olfactory receptors and is responsible for the voluntary movements.

Hence, the correct answer is option (D).

Note: The pallium is thick walled, and it performs various diverse tasks and functions. The different functions of the pallium are associated with higher functions like learning, emotions, intelligence and memory and are also responsible for conscious movements. The pallium forms the roof of the cortex and is associated with higher levels of thinking and intelligence in humans.