Question

Corpus callosum is found in the brain of
A. Elephant
B. Pigeon
C. Crocodile
D. Frog

Answer 1

Hint: Corpus callosum is the white matter present beneath the cerebral cortex that connects the two hemispheres of the brain. It is the largest white matter structure in the brain and with numerous axon projections. It is present in various placental mammals.

Complete step by step answer: Corpus callosum also known as the callosal commissure is the white matter. It has a large C-shaped thick nerve tract consisting of flat bundles of commissural fibres that connect the two hemispheres. Corpus callosum is divided into four main parts: rostrum, genu, body trunk and splenium which connects different parts of the hemispheres. The studies have shown that the average size of the corpus callosum is larger in females and gives differences in different sexes. It is present in placental mammals and absent in marsupials, birds, reptiles, monotremes, amphibians, and fish. Thus, the corpus callosum is present in the elephant from the given options and not in frog, pigeon, and crocodile. The main function of the corpus callosum is to form a connection between two hemispheres and in all different parts of the hemispheres. Several parts of the corpus callosum play a role in this, for e.g., frontal lobes of left and right hemispheres are connected by the rostrum and the genu. It also plays an important role in cognition.
Hence, the correct answer is option A.

Note: A defect in corpus callosum can lead to many cognitive defects and other neurological diseases like akinetic mutism, anomic aphasia, dyslexia, split-brain, multiple sclerosis, septo-optic dysplasia, etc.