regulation of blood glucose concentration

Question 1

What are the three ways to increase blood glucose concentration?

Answer 1

diet, glycogenolysis, gluconeogenisis

Question 2

Explain the process of glycogenolysis?

Answer 2

The breaking down of glycogen in to glucose in the liver and muscle cells and then the glucose is released into the blood to increase blood glucose concentration.

Question 3

What is gluconeogenesis?

Answer 3

The production of glucose from non carb sources e.g. liver makes glucose from lipids and amino acids.

Question 4

What are the two ways to decrease blood glucose concentrations?

Answer 4

respiration and glycogenesis

Question 5

What is glycogenesis?

Answer 5

Glucose is converted to glycogen and stored in the liver

Question 6

How is a high blood glucose concentration detected?

Answer 6

the beta cells in the islets of Langerhans detect it which then secrete insulin directly into bloodstream

Question 7

How does insulin lower blood glucose concentration? (5 methods)

Answer 7

increased rate of absorption of glucose by cells, increases respiratory rate, increased rate of glycogenesis, increased rate of glucose to fat conversion and inhibit release of glucagon by alpha cells.

Question 8

How does glucagon raise blood glucose concentration?

Answer 8

glycogenolysis, reducing amount of glucose absorbed by liver cells, increasing gluconeogenesis

Question 9

How is insulin released?

Answer 9

1. normal glucose levels, potassium channels let potassium ions out of beta cell creating a potential of -70mV
2. glucose levels rise and enter beta cell via glucose transporter
3. glucose is metabolised in mitochondria producing ATP in beta cell
4. ATP binds to potassium channels, closing them
5. potential difference reduces to +30mV and membrane depolarises
6. causing voltage gated calcium channels to open
7. calcium ions enter cell causing secretory vesicles to release insulin via exocytosis.