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Feeling the tremors of an earthquake a scared resident of seventh floor of a multistoreyed building starts climbing down the stairs rapidly. Which hormone initiated this action?
A
adrenaline
B
glucagon
C
gastrin
D
thyroxine
Detailed Solution
Adrenaline (epinephrine) is secreted by the adrenal medulla, along with noradrenaline, in response to stress of any kind and during emergency situations.
It is commonly called the emergency hormone or the hormone of fright, fight or flight (3F hormone).
Its secretion is stimulated by the sympathetic nervous system, not by the pituitary as in the case of the adrenal cortex.
It increases alertness, dilates the pupils, and increases the heart beat, the strength of heart contraction and the rate of breathing; it dilates the coronary artery and the bronchioles.
It also stimulates the breakdown of glycogen, raising the blood glucose, and the breakdown of lipids and proteins, so that extra energy is available to the muscles.
These changes prepare the scared person to run down the stairs rapidly.
So the hormone that initiated this action is adrenaline.
It is commonly called the emergency hormone or the hormone of fright, fight or flight (3F hormone).
Its secretion is stimulated by the sympathetic nervous system, not by the pituitary as in the case of the adrenal cortex.
It increases alertness, dilates the pupils, and increases the heart beat, the strength of heart contraction and the rate of breathing; it dilates the coronary artery and the bronchioles.
It also stimulates the breakdown of glycogen, raising the blood glucose, and the breakdown of lipids and proteins, so that extra energy is available to the muscles.
These changes prepare the scared person to run down the stairs rapidly.
So the hormone that initiated this action is adrenaline.