1. What is homeostasis and why is it important for physiological

functions?

Answer: Homeostasis is the ability of the body to maintain a relatively

constant internal environment despite changes in the external

environment. It is important for physiological functions because it ensures

that the cells and tissues can perform their normal activities within optimal

conditions of temperature, pH, oxygen, glucose, etc.

2. What are the three main components of a feedback system and how do

they work together to regulate physiological functions?

Answer: The three main components of a feedback system are a sensor, a

control center, and an effector. The sensor detects changes in a variable

(such as blood pressure) and sends a signal to the control center (such as

the brain). The control center compares the signal with a set point (the

normal value) and sends a command to the effector (such as the heart).

The effector responds by adjusting the variable back to the set point or

closer to it.

3. What is the difference between positive and negative feedback systems

and give an example of each?

Answer: Positive feedback systems are those that amplify or reinforce the

initial change in a variable, while negative feedback systems are those that

oppose or counteract the initial change in a variable. An example of a

positive feedback system is blood clotting, where the formation of a clot

triggers more clotting factors to be released until the bleeding stops. An

example of a negative feedback system is thermoregulation, where the

body adjusts its heat production and heat loss to maintain a stable body

temperature.