SSC Selection Post 2020 PYQ — Question 28

The correct answer is Option 1 i.e. Medulla oblongata.

• Medulla oblongata controls the beating of the heart and respiratory movement.
• The medulla oblongata, often referred to simply as the medulla, is the lowest segment of the brain and forms the base of the brainstem.
• It appears as a long, stem-like structure situated in front of and slightly below the cerebellum.
• The medulla plays a vital role in regulating involuntary functions, including heartbeat, respiration, and blood pressure.
• The medulla oblongata and the pons in the brain contain three major groups of neurons that regulate respiration. These are collectively known as the respiratory centers:
  • Dorsal Respiratory Group (DRG): primarily involved in controlling the basic rhythm of breathing.
  • Ventral Respiratory Group (VRG): becomes active during forceful breathing and helps in both inspiration and expiration.
  • Pneumotaxic Center: located in the pons, it regulates the rate and pattern of breathing by inhibiting the inspiratory signals.

Other Options:

• Spinal nerves are collections of nerve fibers that link to the spinal cord and are responsible for transmitting signals both to and from it.
• The Spinal cord is a slender, cylindrical structure made of nervous tissue that stretches from the base of the brain along the vertebral column, serving as a vital communication link between the brain and the rest of the body.