How does the body respond following a meal to ensure a relatively constant blood sugar level?
After a meal blood sugar levels will rise. In the Islets of Langerhans beta cells detect hyperglycaemia and secrete insulin, while alpha cells stop releasing glucagon.
The insulin moves in the blood stream to the liver where it binds to receptors on a hepatocyte. The binding of the insulin to a receptor causes a Glut-4 vesicle to move to and fuse with the cell surface membrane by exocytosis. This increases the permeability of glucose into the cell. Glucose is then removed inside the cell by either glycolysis to produce ATP or conversion to Glycogen in glycogenisis.
CJ
Related Biology A Level answers
All answers ▸Compare and contrast the features of eukaryotic DNA and RNA
Explain how an action potential is transmitted from one neurone to another at a synapse.
During large heart attacks the chordae tendineae can be damaged. Use your knowledge of the heart’s structure and the diagram below to to explain how damage to these structures may lead to backflow of blood from the right ventricle to the right atrium.
When a nerve impulse arrives at a synapse, it causes the release of neurotransmitter from vesicles in the presynaptic knob. Describe how.