Thyroxine and Tri-iodothyronine, produced by the thyroid gland, are synthesised from iodine and ___________.
Thyroxine and Triiodothyronine are iodinated form of an amino acid called tyrosine
Which of the following statements regarding glucagon is false?
Glucagon increases blood sugar level. It is secreted by α-cells of islets of Langerhans of pancreas (heterocrine gland).
Which one of the following endocrine glands stores its secretion in the extracellular space before discharging it into the blood?
Thyroid gland stores its hormones in the colloid. Colloid is a homogenous material present in the thyroid follicles of thyroid gland.
Which hormone stimulates the secretion of milk from female?
Prolactin hormone secreted by the anterior lobe of pituitary stimulates the secretion of milk in females.
The hormone which regulates the basal metabolism in our body is secretd from
Thyroid hormones, thyroxine and tri-iodothyronine regulate the basal metabolism of our body.
The gonadotropic hormones are secreted by
Gonadotropic hormones (LH and FSH), secreted by anterior lobe of pituitary regulate growth and activity of gonads.
Secretion of progesterone by corpus luteum is initiated by
Luteinising hormone (LH) secreted by the anterior lobe of pituitary gland stimulates corpus luteum of the ovary to secrete progesterone.
The function of oxytocin is to help in
Oxytocin, secreted by the posterior pituitary gland causes contraction of smooth muscles of the uterus during child birth.
Which part of our body secretes the hormone secretin?
Secretin hormone is secreted by the Brunner's glands present in the wall of the duodenum.
Read the given statements that define functions of a particular hormone.
(i) Regulates the development, maturation and functions of epididymis, vas deferens, seminal vesicle, prostrate gland, urethra, etc.
(ii) Stimulates muscular growth of facial and axillary hair, aggressiveness, low pitch of voice, etc.
(iii) Stimulates spermatogenesis.
(iv) Act on CNS and sexual behaviour (libido).
(v) Produce anabolic (synthetic) effect on protein and carbohydrate metabolism.
(vi) The Leydig's cells/interstitial cells (present in intertubular space) secrete this hormone under the influence of LH.
Which of the following hormones is referred here?
MSH is secreted by
Middle lobe of pituitary secretes MSH (melanocyte stimulating hormone) that controls the synthesis of melanin granules in the chromatophores.
Adrenaline directly affects on
Adrenaline prepares the body for emergency reactions like fight and flight. Therefore, it directly affects the SA node to increase the rate of heart beat.
Sertoli cells are regulated by the pituitary hormone known as
Sertoli cells are regulated by FSH secreted by the anterior pituitary.
Which hormone causes dilation of blood vessels, increased oxygen consumption and glucogenesis?
Adrenaline (Epinephrine) hormone is secreted by adrenal medulla under the conditions of emergency. Therefore, it is also known as emergency hormone. During emergency, it is released and causes dilation of blood vessels, so that the blood flow is increased. It also increases heart beat so that more oxygen is consumed and it also increases blood glucose level.
A person is having problem with calcium and phosphorus metabolism in his body. Which one of the following glands may not be functioning properly?
Parathyroid glands located behind the thyroid gland, produce a hormone called parathormone. This hormone maintains calcium and phosphorus balance in the body. Thus, if a person is having problem with calcium and phosphorus metabolism in the body, this means, his parathyroid gland is not functioning properly.
The blood calcium level is lowered by the deficiency of
Parathormone secreted by parathyroid gland regulates the level of calcium in the blood. It stimulates the release of calcium from the bones into the blood, increases calcium absorption from the intestine into the blood and it also increases calcium reabsorption from the nephrons into the blood. Therefore, its deficiency leads to low blood calcium level.
Diabetes insipidus occurs due to the hyposecretion of
Vasopressin (antidiuretic hormone, ADH) released from posterior pituitary increases reabsorption of water from distal and collecting tubules of the kidney, thus, helping in producing concentrated urine. If there is hyposecretion of vasopressin, then water will not be reabsorbed from the tubules and the urine thus produced will be dilute. This disorder is called diabetes insipidus which is characterised by producing dilute urine several times a day.
Secretion of which of the following is under the control of neurosecretory nerve cells?
The neurosecretory cells of the hypothalamus secrete releasing factors (neurohormones) that regulate the secretion of hormones from the anterior pituitary.
The source of somatostatin is same as that of
Insulin, glucagon and somatostatin, are secreted by islets of Langerhans of pancreas, Somatostatin suppresses the release of other hormones from pancreas.
Which of the following match is correct?
A patient of diabetes mellitus excretes glucose in urine even when he is kept in a carbohydrate free diet. It is because
In diabetes mellitus, a patient is unable to produce or utilise insulin hormone. This hormone helps in maintaining the level of glucose in the blood by converting extra glucose into glycogen. Thus, in diabetes mellitus, the body of the patient becomes incapable to store glucose in the form of glycogen. Therefore, he starts excreting glucose in the urine. If a patient kept on a carbohydrate-free diet is excreting glucose in the urine, then this means, high level of glucose in the blood not only depends on dietary carbohydrates but also on glycogenolysis (breakdown of glycogen into glucose in the liver) and gluconeogenesis(breakdown of fats into glucose in adipose tissues).
Adrenocorticotropic hormone is secreted by
Adrenocorticotropic hormone is secreted by anterior pituitary. This hormone stimulates adrenal cortex to secrete its hormones.
The islets of Langerhans are found in
Islets of Langerhans are found in pancreas. It consists of four types of cells - alpha cells that secrete glucagon, β-cells that secrete insulin, delta cells that secrete somatostatin and F cells that secrete pancreatic polypeptide.
Ovulation in females in under the control of
Ovulation in females is under the control of luteinsing hormone (LH). Secreted by the anterior pituitary gland. It also stimulates development of corpus luteum.
The function of pineal body is to
Pineal body is a very small, reddish-grey, vascular, conical, solid body located in the brain. It secretes a hormone named melatonin. Melatonin makes the skin colour lighter in certain animals and also regulates the functioning of gonads, thus, controls sexual behaviour and regulates the period of puberty.
Goitre is a pathological condition associated with
Goitre is caused due to the deficiency of iodine in the diet. Iodine is needed for the synthesis of thyroxine secreted by thyroid gland. The production of this hormone decreases with poor iodine diet. This causes enlargement of thyroid gland which is called goitre.
Which of the following is not a characteristics of insulin?
Insulin hormone produced by beta cells of pancreas, is central to regulating carbohydrate metabolism in the body. It causes cells in the skeletal muscles, and fat tissue to absorb glucose from the blood.
Which gland atrophies in adults?
Thymus gland is a prominent gland at birth but gradually atrophies in the adult. It is a soft, pinkish, bilobed mass of lymphoid tissue. It secretes a hormone thymosin which is involved in producing immunity.
What is the function of calcitonin?
Calcitonin is a hormone secreted by the thyroid gland. It lowers the calcium level in the blood by suppressing the release of calcium ions from the bones.
Which of the following is called emergency gland of the body?
Adrenal gland secretes adrenaline, and emergency hormone, therefore it is also called emergency gland of the body.
TSH (thyroid stimulating hormone) is produced by
Thyroid stimulating hormone (TSH) is produced by the anterior lobe of the pituitary and it stimulates production and secretion of thyroid hormones.
Increase in bleeding time and delay in blood coagulation is due to the deficiency of which hormone?
Calcium plays an important role in blood clotting. Parathormone, a hormone released by parathyroid glands, increases calcium level in the blood. Therefore, deficiency of this hormone will decrease Ca2+ level in blood, thus leading to delay in blood clotting and increase in bleeding time.
Which of the following hormones is necessary for the development of secondary sexual characters in human beings?
Estrogen, secreted by ovaries in females, stimulates the development of secondary sexual characters during puberty and maintains them through the reproductive years of adult life in females Testosterone is produced by testes in males, it stimulates the development of male secondary sexual characters like beard, moustache, etc.
Which of the following is synthesised in both the brain and endocrine glands?
Somatostatin is an inhibitory hormone which is secreted by hypothalamus in the brain and pancreas. Somatostatin from hypothalamus inhibits the secretion of growth hormone from the anterior lobe of pituitary. Somatostatin from pancreas inhibits the release of other hormones from pancreas like insulin and glucagon.
Which of the following hormones does not have a particular target organ in the body?
Growth hormone secreted by the anterior pituitary has a widespread effect in the body it stimulates growth of various body cells, promotes protein anabolism, absorption of calcium from bowel and conversion of glycogen to glucose.
Besides corticotropin releasing hormone (CRH), which other hormone also stimulates the release of adrenocorticotropic hormone (ACTH)?
Feedback control is a mechanism by which secretion of hormones is under the control of factors or other hormones. When the level of epinephrine decreases in the blood, it stimulates the hypothalamus to secrete more CRH which results in increased production of ACTH from anterior lobe of pituitary which in turn stimulates the increased production of epinephrine from adrenal medulla.
Reabsorption of Na+ is controlled by which one of the following hormones?
Aldosterone (secreted by adrenal medulla) acts mainly on the renal tubules and stimulates the reabsorption of Na+ and water and excretion of K+ and phosphate ions.
Low level of progesterone and estrogen in blood stimulate
When secretion of hormones is under the control of factors or other hormones, it is called the feedback control. If the level of progesterone and estrogen is low in the blood, it stimulates the hypothalamus to secrete more FSH-RH which results in increased production of FSH from anterior pituitary which in turn stimulates the increased secretion of estrogen and progesterone from ovary.
Hormones of which of the following endocrine glands lacks peptides, amines and sulphur?
Hormones of testes and gonads are steroid in nature. They are derived from cholesterol.
Which hormone promotes cell division, protein synthesis and bone growth?
Growth hormone(GH) secreted by anterior pituitary promotes cell division, protein synthesis and bone growth.