What is the difference between a tropic hormone and a direct effector hormone?
a. Tropic and direct effector hormones are both similar in that both act directly on peripheral tissue.
b. Tropic and direct effector hormones are both similar in that both act directly on another endocrine gland.
c. Tropic hormones act on peripheral tissue, while direct effector hormones act on endocrine glands.
d. Tropic hormones act on endocrine glands, while direct effector hormones act on peripheral tissues.
The correct answer and explanation is :
The correct answer is:
d. Tropic hormones act on endocrine glands, while direct effector hormones act on peripheral tissues.
Explanation:
Hormones are chemical messengers secreted by endocrine glands to regulate physiological functions in the body. These hormones can be classified into tropic hormones and direct effector hormones based on their function and target.
Tropic Hormones
- Tropic hormones are hormones that stimulate other endocrine glands to release their hormones.
- They do not directly act on target tissues but rather regulate the secretion of another hormone.
- They are primarily secreted by the anterior pituitary gland.
- Examples:
- Thyroid-Stimulating Hormone (TSH) – Stimulates the thyroid gland to produce thyroxine.
- Adrenocorticotropic Hormone (ACTH) – Stimulates the adrenal cortex to produce cortisol.
- Luteinizing Hormone (LH) – Stimulates the gonads to produce sex hormones.
- Follicle-Stimulating Hormone (FSH) – Stimulates the development of ovarian follicles and sperm production.
Direct Effector Hormones
- These hormones act directly on peripheral tissues or organs to produce a physiological effect.
- They do not require another endocrine gland to mediate their action.
- Examples:
- Insulin – Directly regulates blood glucose levels.
- Growth Hormone (GH) – Stimulates growth and metabolism.
- Oxytocin – Induces uterine contractions and milk ejection.
- Vasopressin (ADH) – Regulates water balance by acting on the kidneys.
In summary, tropic hormones control other endocrine glands, whereas direct effector hormones exert effects on target tissues or organs without requiring an intermediary endocrine gland.
