Correct Option
The correct option is 2 only
Explanation
The adrenal medulla secretes two hormones called adrenaline (epinephrine) and noradrenaline (norepinephrine). These are collectively known as catecholamines. They are often referred to as "emergency hormones" or hormones of "Fight or Flight" because they are rapidly secreted in response to stress of any kind and during emergency situations.
Statement-wise Analysis
- Statement 1 is Incorrect: Catecholamines prepare the body for emergency action. This involves increasing alertness, causing pupillary dilation (to improve vision), piloerection (raising of hairs), and sweating.
- Statement 2 is Correct: These hormones function to mobilize the body's resources for immediate physical activity. Consequently, they increase the heart beat and the strength of heart contraction, rather than decreasing them, to pump more blood to vital organs and muscles.
- Statement 3 is Incorrect: Catecholamines increase the rate of respiration to supply more oxygen. Metabolically, they stimulate the breakdown of glycogen (glycogenolysis), resulting in an increased concentration of glucose in the blood to provide energy. They do not promote glycogen synthesis or reduce the respiratory rate.
Key Takeaway
Catecholamines (Adrenaline and Noradrenaline) stimulate the sympathetic nervous system response, characterized by increased heart rate, increased respiration, pupil dilation, and the mobilization of glucose (glycogenolysis) to facilitate the "Fight or Flight" response.