Note that this topic is for H2 Biology only!

Students should be able to:

(a)   Outline the main stages of cell signalling:

i. ligand-receptor interaction,

ii. signal transduction (phosphorylation cascade and signal amplification)

iii. cellular response (change in gene expression).

(Knowledge of intracellular receptors is not required.)

(b)   Explain the roles and nature of second messengers (including cyclic AMP).

(c) Explain the role of kinases and phosphatases in signal amplification.

(d) Outline how insulin and glucagon regulate the concentration of blood glucose level through the respective tyrosine kinase receptor and G-protein linked receptor.

(The outline should be limited to describing how the ligand induces a conformational change in membrane-bound receptor to trigger downstream signalling pathways that elicit physiological changes in blood glucose level. Details of different second messengers and specific kinases activated in the pathway are not required).