* not completed

. Which of the following statements regarding hormones is correct?

are secreted by exocrine glands correct incorrect

act only on neighbouring cells correct incorrect

are always peptides correct incorrect

are secreted into the blood correct incorrect

* not completed

. Which of the following statements regarding prostaglandins is correct?

are secreted as they are synthesized correct incorrect

are blood-borne chemical signals. correct incorrect

are synthesized from membrane lipids correct incorrect

activate nuclear receptors correct incorrect

* not completed

. Cells use diffusible chemical signals to regulate their own activity

True correct incorrect

False correct incorrect

* not completed

. Which of the following statements regarding hormone receptors is correct?

They have a high affinity for their natural ligand correct incorrect

They are always linked to G proteins correct incorrect

They are lipids correct incorrect

They may be found in the nucleus of their target cells correct incorrect

* not completed

. Complete the following sentence: Activation of heterotrimeric G proteins:

always leads to changes in gene expression correct incorrect

always causes an increase in cyclic AMP correct incorrect

alters the concentration of second messengers correct incorrect

always results in a decrease in cyclic AMP correct incorrect

* not completed

. Which of the following statements about steroid hormones is correct?

Bind to nuclear receptors to regulate gene expression correct incorrect

Activate G protein cascades correct incorrect

Activate receptors on the cell membrane correct incorrect

Directly regulate protein synthesis correct incorrect

* not completed

. Catalytic receptors are membrane-bound protein kinases.

True correct incorrect

False correct incorrect

* not completed

. All signalling molecules are carbon compounds.

True correct incorrect

False correct incorrect