Homeostasis

Question 1

Explain how glucagon increases blood glucose concentration (4)

Answer 1

Glucagon binds to complementary receptor
Causes protein attached to receptor to bind and activate adenylate cyclase
Activated adenylate cyclase converts ATP to cyclic AMP / cAMP
cAMP activates protein kinase which (activates reactions that) breaks down glycogen into glucose

Question 2

Suggest how glucagon receptors on cancer cells encourage growth (2)

Answer 2

Rapidly dividing cancer cells require lots of ATP
Expressing glucagon receptors increase glucose available for respiration