Sella Turcica is found
(a) in bones
(b) in joints
(c) nearby pituitary
(d) nearby thyroid
(a) Sella Turcica is a depression in sphenoid bone of cranial cavity. Pituitary is found in sella turcica.
The source of somatostatin is same as that of
(a) thyroxine and calcitonin
(b) insulin and glucagon
(c) somatotropin and prolactin
(d) vasopressin and oxytocin.
(d): The source of somatostatin is same that of vasopressin and oxytocin. Somatostatin is produced from hypothalamus (somatostatin neuron) and oxytocin and vasopressin are also produced in the nuclei of hypothalamus, though later they are stored and released from posterior pituitary.
Which one of the following four glands is correctly matched with the accompanying description?
(a) Thyroid - hyperactivity in young children causes cretinism
(b) Thymus - starts undergoing atrophy after puberty
(c) Parathyroid - secrets parathormone which promotes movement of calcium ions from blood into bones during calcification
(d) Pancreas - Delta cells of the Islets of Langerhans secrete a hormone which stimulates glycolysis in liver
Cretinism is a type of mental retardation and bodily malformation caused by severe, uncorrected thyroid deficiency in infancy and early childhood. Delta cells is a type of cell in the pancreas (the organ of the digestive system located behind the stomach). Within the pancreas, the delta cells are located in areas called the islets of Langerhans. The delta cells make somatostatin, a hormone that inhibits the release of numerous, hormones in the body. Somatostatin has a variety of functions. Taken together, they work to reduce the rate at which food absorbed from the contents of the intestine. Somatostatin is also secreted by the hypothalamus and by the intestine. Beta cells in the pancreatic islets secrete the hormone insluin in response to a high concentration of glucose in the blood. Parathyroid glands that regulates the metabolism of calcium and phosphate in the body. Parathyroid hormone acts to raise the extracellular calcium concentration, that is, the concentration of calcium ions in the spaces between the cells of the body and in the blood plasma; it promotes the absorption of calcium by the intestine, mobilizes calcium salts from the bones, and increases the tendency of the kidney to recover calcium from the urine. The hormone also enhances both the excretion of phosphate by the kidneys and its uptake by the cells.
Which of the following match is correct
(a) Oxytocin Milk ejection hormone
(b)Glucagon Decreases blood sugar level
(c) Adrenaline Decreases heart rate
(d) Thyroxine Decreases BMR
(a): Oxytocin is a hormone that causes both contraction of smooth muscle in the uterus during birth and expulsion of milk from the mammary glands during suckling. Oxytocin is produced in the neurosecretory cells of the hypothalamus but is stored and secreted by the posterior pituitary gland. Glucagon is a hormone, secreted by the (or A) cells of the islets of Langerhans in the pancreas, that increases the concentration of glucose in the blood by stimulating the metabolic breakdown of glycogen. It thus antagonizes the effects of insulin. Adrenaline (epinephrine) is a hormone produced by the medulla of the adrenal glands, that increases heart activity, improves the power and prolongs the action of muscles, and increases the rate of depth of breathing to prepare the body for 'fright, flight, or fight'. At the same time it inhibits digestion and excretion. Thyroxine is secreted by thyroid gland. It controls the rate of all metabolic processe in the body and influence physical development and activity of the nervous system.
Which of the following statements regarding glucagon is false?
(a) It is secreted by -cells of Langerhans.
(b) It acts antagonistically to insulin.
(c) It decreases blood sugar level.
(d) The gland responsible for its secretion is heterocrine gland
A patient of diabetes mellitus excretes glucose in urine even when he is kept in a carbohydrate free diet. It is because:-
(a) fats are catabolised in adipose tissues to form glucose
(b) amino acids are catabolised in kidney to form glucose
(c) amino acids are discharged in blood stream from liver
(d) glycogen from muscles is released in blood stream
(a) A patient of diabetes mellitus is unable to produce or fail to utilize insulin hormone. Thus, he is unable to store glucose in the form of glycogen. Hence, he started to excrete glucose in the urine. A patient is kept in carbohydrate free diet yet he excretes glucose in urine because high level of glucose not only depends on dietary carbohydrates but also on glycogenolysis (degradation of glycogen in liver) and gluconeogenesis (breakdown of fats into glucose in adipose tissues and coversion of muscle lactate into glucose via cori cycle).
What is the effect of GnRH produced by hypothalamus?
(a) Stimulates the synthesis and secretion of androgens
(b) Stimulates secretion of milk in mammary glands
(c) Stimulates foetal ejection reflex
(d) Stimulates synthesis of carbohydrates from non-carbohydrates in liver
(a): Gonadotropin releasing hormone (GnRH), stimulates the anterior lobe of the pitutary gland to secrete two gonadotropic hormones, follicle stimulating hormone (FSH) and luteinizing hormone(LH). In male LH activates the Leydig's (interstitial) cells of the testis to secrete androgens.
Match the source gland with its respective hormone and function and select the correct option.
Source gland Hormone Function
(a) Anterior pituitary Oxytocin Contraction of uterine muscles
(b) Anterior pituitary Vasopressin Induces reabsorption of water in nephron
(c) Thymus Thymosin Proliferation of T-lymphocytes
(d) -cells of islets Glucagon Uptake of glucose into the cell.
(c) : Oxytocin is released by posterior pituitary. Vasopressin decreases the amount of urine by increasing reabsorption of water from DCT and collecting tubules. It also stimulates the contraction of walls of blood vessels, thereby raising the blood pressure. Glucagon stimulates liver to convert stored glycogen into glucose and thus raises the blood sugar level. Thymus releases thymosin which aids in proliferation of T-lymphocytes.
Select the correct statement about hormones and their actions.
(a) Parathyroid hormone increases absorption of the body.
(b) Insulin and glucagon helps to maintain blood sugar levels.
(c) Old aged people have weak immunity due to increased activity of thymus.
(d) Osteoporosis in women occurs due to increased levels of oestrogens.
(b) Parathyroid hormone (PTH) stimulates the reabsorption of by renal tubules and increases absorption from digested food. It means PTH increases the blood level. Old aged persons have weak immunity because thymus is degenerated in old individuals resulting in a decreased production of thymosin. Osteoporosis in women occurs due to decreased level of estrogen.
Gonadotropin releasing hormone is transferred to anterior pituitary by
(a) left coronary artery
(b) hypophyseal portal veins
(c) axons of neurosecretory cells
(d) nuclei of hypothalamus.
(b): Hypothalamus is connected to the anterior lobe of pitutary gland by hypophyseal portal veins. The latter carry blood containing neurohormones (releasing factors) from the hypothalamus to the anterior lobe of the pituitary.