Question

1. describe the three main components of a negative feedback system and explain how they work together to maintain homeostasis, providing a specific example from the reading passage.

Explanation:

1. Receptor: Detects a deviation from a set point (a change in the internal environment). It sends a signal to the control center.
2. Control Center: Receives the signal from the receptor, compares the detected value to the normal set point, and sends out commands to correct the deviation.
3. Effector: Receives instructions from the control center and carries out a response that reverses the initial deviation, returning the system to the set point to maintain homeostasis.

A common example (consistent with typical biology readings) is human body temperature regulation:

• Receptor: Thermoreceptors in the skin and brain detect a rise in body temperature above 37°C.
• Control Center: The hypothalamus (brain) recognizes the deviation from the set point and sends signals to effectors.
• Effector: Sweat glands activate to produce sweat (which cools the body as it evaporates), and blood vessels in the skin dilate to release heat. Once body temperature returns to 37°C, the receptors signal the hypothalamus to stop the response.

Answer:

The three main components of a negative feedback system are:

1. Receptor: Senses environmental/physiological changes.
2. Control Center: Processes signals, triggers corrective responses.
3. Effector: Carries out actions to reverse deviations.

How they work together: The receptor detects a shift from a normal set point, sends this information to the control center. The control center compares the input to the set point and directs the effector to act. The effector's response reverses the initial change, bringing the system back to the set point, which maintains homeostasis.

Example (body temperature regulation):

• Receptor: Thermoreceptors detect body temp > 37°C.
• Control Center: Hypothalamus identifies the deviation.
• Effector: Sweat glands secrete sweat, skin blood vessels dilate to release heat, lowering body temp back to 37°C, at which point the response stops.