Explanation
Oxytocin, produced by posterior pituitary gland functions in parturition.Melatonin regulates sleep and wake cycles and is secreted by ventricular walls. Melatonin is a hormone from the pineal gland that helps regulate biological rhythms such as sleep and wake cycles. In other words, it's melatonin that directs your internal clock - the one that allows you to wake up about the same time every morning without an alarm clock.Progesterone secreted by corpus luteum is steroid hormone involved in the menstrual cycle, pregnancy and embryogenesis.Atrial natriuretic factor is a powerful vasodilator and a protein hormone, secreted by heart muscle cells.Thus, the correct answer is option B, 'Melatonin - pineal gland, regulates the normal rhythm of sleepwake cycle'.
Islets of Langerhans, also called islands of Langerhans are irregularly shaped patches of endocrine tissue located within the pancreas of most vertebrates. They are named for the German physician Paul Langerhans, who first described them in 1869. The normal human pancreas contains about 1,000,000 islets. The islets consist of four distinct cell types, of which three produce important hormones (alpha cells producing glucagon; beta cells producing insulin and delta cells producing somatostatin). Hormones produced in the islets of Langerhans are secreted directly into the blood flow. The fourth component PP cells secretes pancreatic polypeptide. The combined mass of the islets is 1 to 1.5 grams.
A hormone that stimulates an endocrine gland to grow and secrete its hormone is known as
$$\textbf{Correct option: (D)}$$
$$\textbf{Solution:}$$
$$\textbf{Option (D):}$$
So, the correct answer is option A.
$$\textbf{Correct option:B}$$
$$\textbf{Option (A)}$$
$$\bullet$$ Gonadotropin releasing hormone from hypothalamus stimulates the anterior pituitary to secrete FSH and LH .
$$\bullet$$ FSH helps the graafian follicle development and secretion of estrogens from them ,and sperm production in males.
$$\bullet$$ LH stimulates androgens and progesterone secretion from leydig's cell and corpus luteum respectively.
$$\textbf{Option (B)}$$
$$\bullet$$ The neurosecretory cells of hypothalamus secretes two hormones which are known as neurohormone and they are stored in poterior lobe of pituitary; they are oxytocin and vasopressin or ADH .
$$\bullet$$ Vasopressin increases the permeability of distal convoluted tubules and collecting duct to water in the nephrons. ADH or vasopressin promotes contraction of involuntary muscles in the walls of the intestine, gall bladder and blood vessels and urinary bladder which creates a pressure effect.
$$\bullet$$ Oxytocin promotes the contraction of uterine muscle as it becomes highly sensitive to oxytocin and helps inducing labour at the later stages of pregnancy and promotes parturition.It is also called milk ejecting hormone due to contraction of myoepithelial cells of the lactating breast ,bringing milk from the alveoli to mammary ducts.
$$\textbf{Option (C)}$$
$$\bullet$$ Thyroid stimulating hormone promotes the uptake of iodine by the thyroid glands and stimulates the growth and synthesis of thyroid hormones which are thyroxine and triiodothyronine.
$$\bullet$$ Growth hormone or somatotropin promotes the growth of tissues by protein synthesis and glycogen breakdown.
$$\textbf{Option (D)}$$
$$\bullet$$ Adrenocorticotropic hormones promotes the growth and secretion of adrenal cortex which releases mineralocorticoids,glucacorticoid and sex corticoids.
$$\bullet$$ The intermediate lobe of pituitary secretes melanotropin or melanocyte stimulating hormones which acts on pigmented cells(melanophores) to induce skin colour in certain animals.
$$\textbf{Hence, the correct option is (B)}$$
Please disable the adBlock and continue. Thank you.
