Question

Estrogen, Progestron and relaxim hormones are secreted from

• A. Ovary
• B. Adrenal
• C. Pituitary
• D. Thyroid

Hint:

Remember the ovarian origins of female reproductive hormones:
- Granulosa cells of follicles $\rightarrow$ Estrogen.
- Corpus Luteum $\rightarrow$ Progesterone and Relaxin.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Hormones are chemical messengers synthesized and secreted by endocrine glands to regulate various physiological processes.
The female reproductive system is primarily regulated by steroidal and polypeptide hormones.
These hormones control the estrous cycle, pregnancy, and parturition.

Step 2: Detailed Explanation:
Let us analyze the physiological origin and functions of the listed hormones:
1. Estrogen:
This is a steroid hormone primarily synthesized and secreted by the growing ovarian follicles (specifically the granulosa cells) in the ovaries.
It is responsible for the development of secondary female sexual characteristics, behavioral estrus (heat), and ductal growth in the mammary glands.
2. Progesterone:
This is a steroid hormone synthesized and secreted by the corpus luteum of the ovary during the luteal phase of the estrous cycle and throughout pregnancy.
It is essential for the maintenance of pregnancy (often referred to as the hormone of pregnancy) and alveolar development in the mammary glands.
3. Relaxin:
This is a polypeptide hormone secreted primarily by the corpus luteum of the ovary (and in some species, the placenta) during the late stages of gestation.
It facilitates the relaxation of the pelvic ligaments and cervix to ease the process of parturition (giving birth).
Since all three hormones (estrogen, progesterone, and relaxin) are synthesized and released by different structures within the ovary, the ovary is the correct anatomical source.
Let us briefly review the other endocrine glands listed:
- Adrenal gland: Secretes catecholamines (adrenaline), glucocorticoids (cortisol), and mineralocorticoids (aldosterone).
- Pituitary gland: Secretes gonadotropins (LH, FSH), growth hormone, ACTH, and TSH from the anterior lobe, and oxytocin and ADH from the posterior lobe.
- Thyroid gland: Secretes thyroid hormones (thyroxine, triiodothyronine) and calcitonin.

Step 3: Final Answer:
The hormones estrogen, progesterone, and relaxin are secreted from the ovary.
Therefore, the correct option is (A).