Question

Which body organ is surrounded by meninges?
A. Brain and spinal cord
B. Brain and heart
C. Spinal cord and lungs
D. Heart and lungs

Answer 1

Hint: In physiology, meninges, from Greek “membrane connected to both the skull and vertebrae”. In mammalian, the meninges seem to be the dura mater, the outermost layer is a loosely affiliated fibrous tissue cell layer differentiated by various interlacing cellular events.

Complete answer:
The meninges are the three layers that cover the brain and spinal cord and detach them from walls of their skeletons. Based on the location, meninges are attributed to as cranial meninges covering the brain, and spinal meninges encircling the spinal cord. From surface to extreme, the meninges seem to be the dura mater which is also regarded as pachymeninx, arachnoid mater and pia mater. The role of the meninges is to shield the brain and spinal cord from mechanical injury. It helps the blood vessels and forms a stable cavity by which the cerebrospinal fluid (CSF) runs. Explicitly, the CSF travels between both the inner two meningeal membranes (arachnoid and pia) that are termed leptomeninges. Arachnoid consists of a layer of connective tissue, is avascular, and therefore has no innervation. Below the arachnoid is a vacuum described as subarachnoid space. It comprises the cerebrospinal fluid that functions to cushion the brain. The pia mater is situated near the subarachnoid region. It is quite small and closely bound to the membrane of the brain and the spinal cord. This is the only cover to follow the curvature of the brain.
So, the correct answer is option (A).

Additional Information: Injuries causing meninges may end in internal bleeding and different kinds of a hematoma. Subarachnoid bleeding is intense bleeding underneath the arachnoid; it can naturally occur or even as a result of trauma. Subdural hematoma found in the division of the arachnoid from the dura mater. The tiny veins which attach the dura mater to the arachnoid are ripped, normally in an accident, and blood spills into this area.

Note: Meninges are the tissues of the brain and spine. The meninges are sequentially arranged membranes used to completely cover and safeguard the central nervous system (CNS). Meninges have collagen and elastic fibres. It serves to anchor the CNS in place to protect, for example, the brain from wandering all around the skull.