Copy the diagram given below. 
(a) Name the structure.
(b) Label Gray matter and White matter.
(a) Name the structure.
The structure shown in the diagram is the {Cross-section of the Spinal Cord}. The spinal cord is a crucial part of the central nervous system that transmits neural signals between the brain and the rest of the body.
(b) Label Gray matter and White matter.
In the diagram, the {Gray matter} is located in the central region of the spinal cord, resembling a butterfly shape. It consists of neuron cell bodies, dendrites, and unmyelinated axons.
The {White matter} surrounds the gray matter and contains myelinated axons that transmit signals along the spinal cord.
শ্রবণ কেন্দ্র” বা “মিক্সরেশন সেন্টার” উপস্থিত
Karan was standing on a high stool and cleaning the ceiling fan.
He suddenly loses balance and sustains a head injury. An examination reveals that his pupils have lost the capacity to constrict in bright light. Which structure has been damaged?
Bharat woke up late in the morning and missed the school bus.
This situation stimulated the nerves of the sympathetic system which resulted in: 


During the ventricular systole, the atrioventricular valves (P) ________ and the semilunar valves (Q) _________.