Hormonal Communcation

Question 1

What are the four main modes of hormonal communication?

Answer 1

Endocrine.
Paracrine.
Communication between membrane receptors.
Autocrine communication.

Question 2

What is endocrine communication?

Answer 2

When a hormone travels within blood vessels to act on a distant target cell.
(E.g. glucagon from the pancreas acting on the liver)

Question 3

What is paracrine communication?

Answer 3

When a hormone acts on an adjacent cell.

E.g. insulin produced by beta cells inhibiting glucagon secretion on neighbouring alpha cells

Question 4

Give an example of communication between membrane receptors.

Answer 4

When antigen-presenting cells express MHC II and bind with circulating T cells.

Question 5

What is autocrine communication?

Answer 5

When a signalling molecule acts on the same cell it was made in.
(E.g. T cell receptors expressing IL-2 receptors when activated and then producing IL-2 to bind to them or cell signalling involving apoptosis).