In the endocrine regulation of blood glucose, the hormones adrenaline and glucagon coordinate glycogen breakdown in hepatocytes via a second messenger pathway. Which of the following correctly describes the sequence of molecular events during this process?
The hormone binds to a specific cell-surface receptor, activating adenylate cyclase. This enzyme converts ATP to cyclic AMP (cAMP), which acts as a second messenger to activate protein kinase, leading to glycogen hydrolysis.
The hormone binds to a specific cell-surface receptor, activating protein kinase. Protein kinase converts ATP to cyclic AMP (cAMP), which acts as a second messenger to activate adenylate cyclase, leading to glycogen hydrolysis.
The lipid-soluble hormone crosses the cell membrane and binds to an intracellular receptor, activating adenylate cyclase. This enzyme converts cyclic AMP (cAMP) to ATP, which directly phosphorylates glycogen to release glucose.
The hormone binds to a specific cell-surface receptor, activating adenylate cyclase. This enzyme converts cyclic AMP (cAMP) to ATP, which acts as a second messenger to activate protein kinase, leading to glycogen hydrolysis.
Practise OCR GCSE Biology Coordination and control – the endocrine system with exam-style questions for Foundation and Higher tier. 52 questions, matched to the OCR GCSE Biology (J247) specification and written in the written papers style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.