Ventricle-definition and parts

The cavities or chambers of the brain are called ventricles. There are 4 ventricles in the brain. namely first, second, third and fourth ventricles.
1. Lateral Ventricles: The 1st and 2nd ventricles of the brain are collectively called the lateral ventricles. There are two cavities inside the cerebral hemispheres. These two cavities are called lateral ventricles. They are individually connected to the 3rd ventricle by the foramen of Monro or interventricular orifice.
2. Third ventricle: The cavity of hypothalamus is called third ventricle. One end of it is connected to the 3rd ventricle.
3. Fourth Ventricle: The cavity of the medulla oblongata is called the fourth ventricle. One end is connected to the cerebral aqueduct and the other end to the central canal of the spinal cord.

Functions of medulla oblongata

(i) It acts as a control center for respiration, digestion, constriction of blood vessels, secretion of saliva, heartbeat etc.
(ii) regulates blood pressure, defecation, alimentary canal peristalsis etc. (RRAR) Protects the connection between the brain and the nervous system.
(iii) It gives rise to the 9th, 10th and 11th carotid nerves and controls various functions.

Medulla oblongata-definition and functions

The pyramidal shaped part located below the pons is called the medulla oblongata. Its length is about 3 cm, width 2 cm and thickness 1.2 cm.
Functions of the medulla oblongata
(i) It acts as a control center for respiration, digestion, constriction of blood vessels, secretion of saliva, heartbeat etc.
(ii) regulates blood pressure, defecation, alimentary canal peristalsis etc. (RRAR) Protects the connection between the brain and the nervous system.
(iii) It gives rise to the 9th, 10th and 11th carotid nerves and controls various functions.