Question

A chemical signal that has both endocrine and neural roles is

• A. cortisol
• B. epinephrine
• C. calcitonin
• D. melatonin

Answer 1

The correct option is B

epinephrine

The correct option is B.

Explanation of correct option:

1. Hormones act as chemical signals that are released from the endocrine glands present in the body.
2. The adrenal medulla secretes two hormones called epinephrine (adrenaline) and norepinephrine (noradrenaline).
3. These hormones are secreted in response to stress and emergency situations.
4. They increase heart rate, pupillary dilation, blood glucose levels, respiration rate, etc.
5. These hormones also act as neurotransmitters.

Explanation of incorrect option:

Option A:

1. Cortisol is a glucocorticoid secreted by the adrenal cortex.
2. They are known to stimulate lipolysis and gluconeogenesis.

Option C:

1. Calcitonin is a protein hormone secreted by the thyroid gland.
2. It helps in regulating calcium levels in the blood.

Option D:

1. Melatonin is a hormone secreted by the pineal gland.
2. It plays a vital role in maintaining the diurnal rhythm of the body.

Final answer: A chemical signal that has both endocrine and neural roles is epinephrine.