Human Endocrine System

Step 1: Understanding Grave’s disease.
Grave’s disease is an autoimmune disorder that affects the thyroid, leading to symptoms like increased blood pressure, heart rate, weight loss, and fat deposition around the eyes.
Step 2: Analyzing the options.
(A) Addison’s disease: Incorrect. Addison's disease is characterized by adrenal insufficiency, which leads to fatigue, weight loss, and skin darkening, not the symptoms described.
(B) Grave’s disease: Correct. Grave’s disease leads to hyperthyroidism and the symptoms described in the question.
(C) Bleeder’s disease: Incorrect. Bleeder's disease, or hemophilia, is a clotting disorder and does not cause the symptoms mentioned.
(D) Cushing’s disease: Incorrect. Cushing’s disease leads to symptoms like weight gain, not weight loss or fat deposition in the eye sockets.
Step 3: Conclusion.
The correct answer is (B) Grave’s disease, as it is associated with the symptoms described in the question.

Step 1: Dual-origin glands are those that develop from two different embryonic tissues. The adrenal gland develops from both mesoderm and neural crest cells, while the pituitary gland has two parts: the anterior part arises from the ectoderm, and the posterior part arises from neural tissue.

Step 2:
- (A) Adrenal gland and Placenta: The adrenal gland is dual in origin, but the placenta develops entirely from the trophoblast and maternal tissues.
- (C) Thyroid gland and Pituitary gland: The thyroid gland develops from endoderm, and the pituitary from ectoderm and neural tissue, but it is not considered dual in origin.
- (D) Pituitary gland and pineal gland: The pituitary is dual in origin, but the pineal gland arises from the ectoderm.

Conclusion: The pituitary gland and adrenal gland are dual in origin, making the correct answer.

Step 1: The adrenal cortex is divided into three layers: - Zona glomerulosa (outermost) produces mineralocorticoids. - Zona fasciculata (middle layer) produces glucocorticoids, such as cortisol. - Zona reticularis (innermost) produces sex hormones.
Step 2: - (A) Zona reticularis produces sex hormones, not glucocorticoids.
- (B) Zona glomerulosa produces mineralocorticoids.
- (D) The medulla is the inner part of the adrenal gland, responsible for producing catecholamines.
Conclusion: The middle layer of the adrenal cortex is the zona fasciculata.

Gibberellins are plant hormones that promote cell elongation and division, enhancing fruit size. Uses include: \begin{itemize} \item Increasing the size of grapes and apples. \item Stimulating seed germination and stem elongation. \end{itemize} Auxins and cytokinins are involved in growth but are less specific to fruit enlargement. --- Final Answer:

The anterior pituitary gland secretes several hormones that regulate various physiological processes. Among these, thyroid-stimulating hormone (TSH) specifically targets the thyroid gland, stimulating it to produce and release thyroxine (T4) and triiodothyronine (T3). These thyroid hormones regulate metabolism, growth, and development.
The other hormones listed have different functions:
- Adrenocorticotropic hormone (ACTH): Stimulates the adrenal cortex to release corticosteroids, such as cortisol, which regulate stress response and metabolism.
- Follicle-stimulating hormone (FSH): Stimulates the development of ovarian follicles in females and spermatogenesis in males.
- Luteinizing hormone (LH): Triggers ovulation and the formation of the corpus luteum in females and stimulates testosterone production in males.
Thus, the hormone secreted by the anterior pituitary gland that stimulates the thyroid gland is thyroid-stimulating hormone (TSH).