GENERAL HISTOLOGY

Detailed explanation-1: -(b) Body temperature is regulated by negative feedback. The stimulus is when the body temperature exceeds 37 degrees Celsius, the sensors are the nerve cells with endings in the skin and brain, the control is the temperature regulatory center in the brain, and the effector is the sweat glands throughout the body.

Detailed explanation-2: -(b) Body temperature is regulated by negative feedback. In order to set the system in motion, a stimulus must drive a physiological parameter beyond its normal range (that is, beyond homeostasis). This stimulus is “heard” by a specific sensor.

Detailed explanation-3: -Thermoregulation is an example of negative feedback. The hypothalamus in the brain is the master switch that works as a thermostat to regulate the body’s core temperature (Figure 1).

Detailed explanation-4: -Negative feedback-example If the hypothalamus detects that the body is too hot, the response is that the body begins to sweat to try and reduce the temperature back to the correct level. Once the body temperature is back to the correct level, sweating will stop.

Detailed explanation-5: -Another example of negative feedback is the regulation of the blood calcium level. The parathyroid glands secrete parathyroid hormone, which regulates the level of calcium in the blood. If calcium decreases, the parathyroid glands sense the decrease and secrete more parathyroid hormone.