Module 2: Factors influencing chemical messengers

Question 1

What are the 3 factors that effect chemical messengers

Answer 1

1. Concentration of messengers
2. Affinity of receptors for chemical messengers
3. Number of receptors

Question 2

How does the concentration of messengers effect them

Answer 2

increase in concentration of the messenger will cause an increase in the percentage of receptors bound, producing a greater response

Question 3

How does affinity of receptors for chemical messengers effect them

Answer 3

a receptor with a higher affinity for that chemical messenger has an increased rate of binding, therefore increased response

Question 4

How does the number of receptors effect the chemical messengers

Answer 4

the more available receptors for the chemical messenger, the greater the effect will be

Question 5

What is upregulation

Answer 5

total number of receptors bound increase

Question 6

What is down regulation

Answer 6

total number of receptors bound decrease

Question 7

What is the effect of upregulation

Answer 7

when a cell increases number of receptors on its surface it becomes more sensitive to a hormone or drug

Question 8

What is the effect of down regulation

Answer 8

when a cell decreases the number of receptors on its surface it becomes less sensitive, this is what causes drug users to build up a tolerance