Question

Which hormone causes dilation of blood vessels, increased oxygen consumption and glycogenolysis?

• A. ACTH
• B. Insulin
• C. Adrenalin
• D. Glucagon

Answer 1

The Correct Option is C

To determine which hormone causes dilation of blood vessels, increased oxygen consumption, and glycogenolysis, let's examine each of the given options:

1. ACTH (Adrenocorticotropic Hormone): This hormone is primarily involved in stimulating the adrenal cortex to secrete glucocorticoids, such as cortisol. It does not directly cause blood vessel dilation, increased oxygen consumption, or glycogenolysis.
2. Insulin: Produced by the pancreas, insulin helps regulate blood glucose levels by facilitating the uptake of glucose into cells and promoting glycogen synthesis. Insulin does not directly cause dilation of blood vessels or increased oxygen consumption.
3. Adrenalin (Epinephrine): Adrenalin is a hormone secreted by the adrenal medulla. It plays a crucial role in the body's fight-or-flight response. This hormone causes vasodilation in certain blood vessels, increases heart rate and oxygen consumption, and stimulates glycogenolysis, which breaks down glycogen into glucose for use by the body.
4. Glucagon: Secreted by the pancreas, glucagon's main function is to raise blood glucose levels by promoting glycogenolysis and gluconeogenesis, but it does not cause dilation of blood vessels or significant effects on oxygen consumption.

Based on the above analysis, the correct answer is Adrenalin. Adrenalin is responsible for causing vasodilation in certain arterioles, increasing oxygen consumption due to its effects on heart rate and metabolic rate, and promoting glycogenolysis to increase glucose availability in the bloodstream.