NEET Practice Questions (MCQs) with Answers & Solutions

The limbic system, which includes structures such as the hippocampus, amygdala, and parts of the thalamus, is closely associated with the hypothalamus. The hypothalamus plays a crucial role in many autonomic functions of the body, including the regulation of sexual behavior. Therefore, the limbic system in conjunction with the hypothalamus regulates sexual behavior.

The midbrain, also known as the mesencephalon, is located between the diencephalon (which includes structures such as the thalamus and hypothalamus) and the pons. Understanding the anatomical positioning of the midbrain is crucial for comprehending its role in neural pathways and functions.

The cerebral aqueduct, also known as the aqueduct of Sylvius, is a narrow channel that passes through the midbrain. It connects the third ventricle, located in the diencephalon, to the fourth ventricle, which is situated between the pons and the medulla oblongata. This pathway is essential for the circulation of cerebrospinal fluid within the brain's ventricular system.

The corpora quadrigemina are located on the dorsal (posterior) surface of the midbrain. They consist of four colliculi—two superior and two inferior—that are involved in visual and auditory reflexes, respectively.

The superior colliculi are part of the midbrain and are primarily involved in the control of visual reflexes. They help in the coordination of eye movements and the processing of visual stimuli.

The secretion of saliva on seeing tasty food is a conditioned reflex, which is different from the other options listed. Antiperistalsis, peristalsis, and heart-beat are all examples of unconditioned reflexes, which occur naturally without prior learning.

Conditioned reflexes are learned responses to stimuli, often through repeated association. Prejudices (1), Dis-liking (4), and Habits (5) are all examples of such learned responses, making option 3 correct.

The stiff edge of the pinna is called the Helix. The Helix is the outermost rim of the ear, which is curved and forms the contour of the pinna.