Hormones and the control of blood glucose concentration：練習問題

Which hormone is primarily responsible for activating enzymes that convert glycogen to glucose (glycogenolysis) in the liver when blood glucose levels are low?

In the second messenger model of hormone action, what is the specific role of the enzyme adenyl cyclase when adrenaline binds to its receptor?

Which of the following best explains how insulin reduces blood glucose concentration after a meal?

Which of the following processes involves the liver converting non-carbohydrates, such as glycerol and amino acids, into glucose?

Explain how the second messenger model is used by glucagon to trigger the hydrolysis of glycogen in liver cells.

A patient is diagnosed with Type 2 diabetes. Despite high levels of insulin in the blood, their blood glucose remains elevated.

Suggest how a defect in the signal transduction pathway, following the binding of insulin to its receptor, prevents the lowering of blood glucose levels.

When blood glucose concentration falls, glucagon is secreted by the pancreas.

Identify two specific non-carbohydrate sources that can be converted into glucose by the liver under the influence of this hormone.

Blood glucose levels are strictly regulated by the pancreas to ensure cellular energy needs are met while maintaining blood water potential.

(a) Name the specific endocrine tissue in the pancreas responsible for the production of glucose-regulating hormones.
(b) Identify the specific cells within this tissue that secrete insulin and glucagon.
(c) State two ways in which glucose is added to the blood during the normal daily cycle of a healthy individual.

A student investigates the hormonal response to a high-carbohydrate meal in a healthy volunteer. Within 60 minutes, the blood glucose concentration rises and then begins to return to its original level due to the action of insulin.

(a) Describe how insulin leads to the inclusion of more glucose transport proteins (GLUT4) in the surface membranes of target cells.
(b) Aside from membrane transport, explain how insulin affects intracellular enzymes to ensure blood glucose remains low.
(c) Suggest why a failure in this regulatory mechanism could lead to dehydration of the body's cells.