Different glands and their hormones Questions in English

(C) Gonads and pancreas are included under heterocrine glands.
Heterocrine glands,also known as mixed glands,perform both exocrine and endocrine functions.
Exocrine glands release their secretions through ducts,whereas endocrine glands release their secretions directly into the blood without ducts.
Heterocrine glands release their secretions through a duct system as well as directly into the blood.
Thyroid,parathyroid,pineal,and thymus glands are purely endocrine in function.

(B) During an allergic reaction,$histamine$ is released,which acts as a vasodilator. This increases plasma flow and leads to the narrowing of the lumen of the bronchioles,causing difficulty in breathing,which is characteristic of asthma.
Adrenaline (epinephrine) is administered because it acts as a potent bronchodilator and vasoconstrictor. It relaxes the smooth muscles of the bronchioles,thereby widening the airway and providing relief in exhaling the air.

(A) Exocrine glands secrete their products through ducts. The products listed are: Mucus,Saliva,Earwax,Oil,Milk,and Digestive enzymes. Total count of $P = 6$.
Endocrine glands are ductless and secrete hormones directly into the blood. The products listed are: Prolactin and Testosterone. Total count of $Q = 2$.
Therefore,$P = 6$ and $Q = 2$.

(C) Glands are classified into two types based on the presence or absence of ducts:
$1$. Exocrine glands: These glands possess ducts to transport their secretions (e.g.,salivary glands,sweat glands).
$2$. Endocrine glands: These are ductless glands that secrete their products,known as hormones,directly into the bloodstream.
Therefore,endocrine glands are ductless glands.

(A) The Gonadotropin-Releasing Hormone $(GnRH)$ is a peptide hormone synthesized and secreted by the hypothalamus.
It travels to the anterior pituitary gland via the hypophyseal portal system.
In response to $GnRH$,the anterior pituitary gland secretes gonadotropins,which include Luteinizing Hormone $(LH)$ and Follicle-Stimulating Hormone $(FSH)$.
Therefore,$GnRH$ is secreted by the hypothalamus and gonadotropins are secreted by the pituitary gland.

(C) The correct answer is option $C$ because glucagon is a peptide (proteinaceous) hormone secreted by the alpha cells of the pancreas.
Steroid hormones are derived from cholesterol. Testosterone,progesterone,and cortisol are all steroid hormones.
Therefore,glucagon is the only hormone listed that is not a steroid hormone.

(A) The correct matching is as follows:
$A.$ Progesterone is secreted by the $IV.$ Corpus luteum.
$B.$ Relaxin is produced by the $II.$ Ovary (specifically during pregnancy).
$C.$ Melanocyte stimulating hormone $(MSH)$ is secreted by the $I.$ Pars intermedia of the pituitary gland.
$D.$ Catecholamines (Adrenaline and Noradrenaline) are secreted by the $III.$ Adrenal Medulla.
Therefore,the correct sequence is $A-IV, B-II, C-I, D-III$.

(A) Option $A$ is correct. Norepinephrine is secreted by the adrenal medulla and acts as a neurotransmitter and hormone that increases heart rate,respiratory rate,and alertness during stress.
Option $B$ is incorrect because Glucagon is secreted by the Alpha-cells,not Beta-cells.
Option $C$ is incorrect because Prolactin is secreted by the Anterior pituitary,not the Posterior pituitary.
Option $D$ is incorrect because Vasopressin $(ADH)$ decreases the loss of water through urine by promoting water reabsorption in the kidneys.

(B) Glycolysis is the metabolic pathway that converts glucose into pyruvate.
In the human body,blood glucose levels are tightly regulated by hormones.
$Glucagon$ increases blood glucose levels by stimulating glycogenolysis and gluconeogenesis.
$Insulin$ decreases blood glucose levels by promoting glucose uptake into cells and stimulating glycolysis.
$Epinephrine$ (adrenaline) also stimulates glycogenolysis and glycolysis in muscles to provide energy during stress.
Therefore,$Glucagon$,$epinephrine$,and $insulin$ are the primary hormones involved in the regulation of glucose metabolism and glycolysis.

(D) $i$. Graves disease is caused by the hypersecretion of thyroid hormones.
$ii$. Cushing's disease is caused by the hypersecretion of glucocorticoids.
$iii$. Acromegaly is caused by the hypersecretion of growth hormone (somatotropin) in adults.
$iv$. Diabetes insipidus is caused by the deficiency (hyposecretion) of Antidiuretic Hormone $(ADH)$ or vasopressin. Therefore,the correct match is $D$.

(C) $i$. $ADH$ acts on the distal convoluted tubule and collecting ducts of the kidney to facilitate water reabsorption.
$ii$. Oxytocin acts on the smooth muscles of the uterus to cause contractions and on the mammary glands to stimulate milk ejection.
$iii$. Relaxin is produced by the corpus luteum and placenta,and it acts on the cervix of the uterus to soften and dilate it during childbirth.
$iv$. Secretin acts primarily on the pancreas to stimulate the secretion of water and bicarbonate ions,and on the liver to stimulate bile secretion.

(C) The correct match for the salt-retaining hormone is Aldosterone,which is secreted by the adrenal cortex. Thyroxine is primarily responsible for regulating the basal metabolic rate,not salt retention. Therefore,the pair 'Salt retaining hormone - Thyroxine' is the mismatch.

(A) The correct answer is $A$.
Parathyroid hormone $(PTH)$ and Thyrocalcitonin $(TCT)$ are the two hormones responsible for maintaining calcium homeostasis in the human body.
$PTH$ is secreted by the parathyroid glands and is a hypercalcemic hormone,meaning it increases blood $Ca^{2+}$ levels by stimulating bone resorption,renal reabsorption of $Ca^{2+}$,and intestinal absorption of $Ca^{2+}$.
$TCT$ is secreted by the thyroid gland and is a hypocalcemic hormone,which lowers blood $Ca^{2+}$ levels.
Together,these two hormones act antagonistically to maintain the precise balance of calcium in the blood.

(B) is the incorrect pair.
$Gluconeogenesis$ is the process of synthesizing glucose from non-carbohydrate sources like amino acids and glycerol.
$Insulin$ is a hypoglycemic hormone that promotes $glycogenesis$ (conversion of glucose to glycogen) and glucose uptake by cells,thereby lowering blood glucose levels.
$Gluconeogenesis$ is actually promoted by hormones like $glucagon$ and $cortisol$.

(A) is the mismatched pair.
Insulin is a hormone that lowers blood glucose levels by primarily promoting glucose uptake into cells and glycogen synthesis,while simultaneously inhibiting gluconeogenesis.
Gluconeogenesis,which is the synthesis of glucose from non-carbohydrate sources,is stimulated by hormones like glucagon and cortisol,not insulin.

(A) Estrogen.
Steroid hormones are derived from cholesterol. Examples include estrogens,androgens,and glucocorticoids.
Estrogens are involved in regulating secondary sexual characteristics in females,the menstrual cycle,and the overall health of the reproductive system.
Insulin and Glucagon are peptide hormones,while Thyroxine is an amino acid derivative (iodinated tyrosine).

(C) The correct answer is $C$.
Insulin is a hypoglycemic hormone that lowers blood glucose levels.
It increases the permeability of cell membranes to glucose and promotes the oxidation of glucose in cells.
It also stimulates glycogenesis,which is the formation of glycogen from excess glucose in the liver and muscles.
Option $C$ is incorrect because the conversion of glycogen to glucose (glycogenolysis) is stimulated by the hormone glucagon,not insulin.

(C) Prostaglandin.
Prostaglandins are not polypeptides; they are lipid compounds derived from fatty acids.
Insulin,antidiuretic hormone $(ADH)$,and oxytocin are all peptide hormones,which are composed of amino acids.

(C) The correct option is $C$.
$A$ represents $GnRH$ (Gonadotropin-releasing hormone),which is secreted by the hypothalamus.
$GnRH$ stimulates the anterior pituitary gland to release gonadotropins,which are $FSH$ (Follicle-stimulating hormone) and $LH$ (Luteinizing hormone).
$B$ represents $FSH$,which acts on the ovaries to stimulate the growth of ovarian follicles.
$C$ represents $LH$,which acts on the testes to stimulate Leydig cells to secrete androgens (testosterone).