Question

Spinal cord originates from
(a) Cerebrum
(b) Pons
(c) Medulla
(d) Cerebellum

Answer 1

Hint: Posterior most part of the brain that leaves from foramen magnum which is extended from the pons. It is a part of the hindbrain.

Complete answer:
The spinal cord is located in the vertebral canal of the backbone or vertebral column which is protected by the bony arch. It originates from the last part of the hindbrain called the medulla oblongata which passes out of the cranium through a hole called the foramen magnum and joins the spinal cord. This spinal cord extends from the medulla oblongata to the second lumbar vertebrae.

Additional information:
- Human brain is divided into the forebrain, midbrain, and hindbrain
- Forebrain consists of the olfactory bulb, cerebrum, and diencephalon
- Midbrain consists of cerebral peduncles, a pair of longitudinal bands of nervous tissue.
- Cerebellum, pons, and medulla oblongata are present in the hindbrain
- Medulla oblongata leaves the cranium through the foramen magnum and joins the spinal cord.
- Spinal cord extends from the medulla oblongata to the second lumbar vertebrae
- It has two enlargements, superior enlargement is called cervical enlargement and inferior enlargement is called lumbar enlargement.
- Spinal cord is divided into two hemispheres by a median fissure on the anterior side and median sulcus on the posterior side
- When a spinal cord is cut laterally, it shows an H-shaped or butterfly-shaped central area of grey matter surrounded by white matter.
- the nerves that arise from the spinal cord are 31 pairs called spinal nerves.
- It acts as a coordinating center for simple spinal reflexes and acts as a mediator between receptors and effector cells.

Note:
- The three layers that cover the spinal cord are dura mater, arachnoid mater, and pia mater which are collectively called spinal meninges.
- In the brain, the inner region is white matter surrounded by grey matter but in the spinal cord, it is vice versa.