Hormonal control

Question 1

Insulin

Answer 1

Stimulates uptake and use of glucose and storage as glycogen and fat (islets of Langerhans)

Question 2

Glucagon

Answer 2

Stimulates production of glucose

Question 3

Adrenalin

Answer 3

Strong, fast metabolic effects to mobilise glucose for “flight or fight”

Question 4

Glucocorticoids

Answer 4

Steroid hormones, increase synthesis of metabolic enzymes concerned with glucose availability.

Question 5

After prolonged fasting

Answer 5

• Glucagon/insulin ratio increases further
• Adipose tissue begins to hydrolyse triglyceride to provide fatty acids for metabolism
• TCA cycle intermediates are reduced in amount to provide substrate for gluconeogenesis
• Protein breakdown provides amino acid substrates for gluconeogenesis
• Ketone bodies are produced from fatty acids and amino acids in liver to substitute partially the brain’s requirement for glucose