Question

once the body has begun shivering, what happens to make it stop shivering?
○ when body temperature returns to normal, the respiratory system sends a message to the skeletal system to stop shivering.
○ when body temperature returns to normal, the nervous system sends a message to the muscular system to stop shivering.
○ when body temperature is below normal, the nervous system sends a message to the skeletal system to stop shivering.
○ when body temperature is below normal, the respiratory system sends a message to the muscular system to stop shivering.

Explanation:

Shivering is a muscular response (by skeletal muscles) to low body temperature, controlled by the nervous system. When body temperature returns to normal, the nervous system (which regulates body functions including temperature and muscle activity) sends a signal to the muscular system to stop shivering. Let's analyze each option:

• First option: Respiratory system doesn't control muscle shivering; skeletal system is not the controller here. Eliminate.
• Second option: Correct. Nervous system (regulatory) sends message to muscular system (shivering is muscle activity) when temp normalizes.
• Third option: Shivering stops when temp is normal, not below. Also, skeletal system isn't the sender. Eliminate.
• Fourth option: Respiratory system isn't involved, and temp is below (should be normal). Eliminate.

Answer:

B. When body temperature returns to normal, the nervous system sends a message to the muscular system to stop shivering.