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

Which hormone causes dilation of blood vessels, increased oxygen consumption and glycogenolysis ?
A ACTH
B Insulin
C Adrenalin
D Glucagon

Detailed Solution

Adrenaline (epinephrine) is secreted by the adrenal medulla during stress and emergency; it is called the emergency hormone or the hormone of fight or flight.
It dilates the blood vessels of the skeletal muscles, heart and liver, so that more blood reaches them, and it dilates the bronchioles.
It increases the heart beat, the rate of respiration and the metabolic rate, so the consumption of oxygen increases.
It stimulates the breakdown of glycogen (glycogenolysis) in the liver and muscles, raising the blood glucose level.
Glucagon also causes glycogenolysis, but it does not dilate blood vessels or increase oxygen consumption in this way.
Insulin lowers blood glucose by promoting glycogenesis, and ACTH stimulates the adrenal cortex.
So the hormone is adrenalin.

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