#1 of 44
SZABMU 2024
Permalink
Which of the following gland/s is/are mostly responsible for releasing stress hormones?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The human body relies on a specialized pair of glands situated atop the kidneys to manage both acute and chronic stress.
Solution:- The adrenal glands are structurally divided into two parts that both handle stress:
- The inner medulla releases epinephrine (adrenaline) to handle immediate, life-threatening "fight-or-flight" stress.
- The outer cortex releases cortisol (a glucocorticoid) to manage long-term, chronic stress.
Why other options are incorrect:The pituitary commands the adrenals but doesn't release the final stress effectors. The thyroid controls basal metabolism.
#2 of 44
SZABMU 2024 Reconduct
Permalink
Which pathway will be followed by water soluble hormone for crossing plasma membrane?
A
Receptor \(\rightarrow\) 2nd messenger \(\rightarrow\) Activation of energy
B
2nd messenger \(\rightarrow\) Receptor \(\rightarrow\) Activation of energy
C
Activation of energy \(\rightarrow\) Receptor \(\rightarrow\) 2nd messenger
D
Receptor \(\rightarrow\) Activation of energy \(\rightarrow\) 2nd messenger
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Hormone signaling mechanisms depend entirely on whether the hormone is lipid-soluble (can penetrate membranes) or water-soluble (cannot penetrate).
Solution:- Because water-soluble (peptide) hormones cannot push through the hydrophobic lipid bilayer, they must bind to a surface Receptor.
- This binding activates an intracellular 2nd messenger molecule (like cyclic AMP).
- The 2nd messenger then cascades through the cytoplasm, resulting in the Activation of cellular enzymes/energy to alter the cell's function.
Why other options are incorrect:The order is strictly chronological: outside receptor first, inside messenger second, physiological change last.
#3 of 44
SZABMU 2024 Reconduct
Permalink
Which is a steroid hormone?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Steroid hormones are synthesized exclusively by the gonads, placenta, and adrenal cortex.
Solution:- Cortisone is a powerful glucocorticoid produced in the adrenal cortex.
- Because its chemical backbone is constructed from cholesterol, it falls squarely into the steroid classification.
Why other options are incorrect:Insulin is a large protein. Adrenaline and thyroxin are modified amino acids (amines). None of these share the 4-ring cholesterol structure of a steroid.
#4 of 44
SZABMU 2024
Permalink
Which of the following hormone has the greater influence on peripheral vasoconstriction?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Blood pressure regulation during shock or stress relies on the constriction of peripheral blood vessels to shunt blood to vital organs.
Solution:- While adrenaline (epinephrine) dilates vessels in skeletal muscle, Norepinephrine (noradrenaline) has an incredibly high affinity for alpha-1 adrenergic receptors located on the smooth muscle of peripheral blood vessels.
- This causes profound and widespread peripheral vasoconstriction, dramatically spiking blood pressure.
Why other options are incorrect:Epinephrine has mixed dilatory and constrictive effects. Parathormone regulates calcium. Corticosteroids manage long-term stress and metabolism.
#5 of 44
NUMS 2024
Permalink
Which disorder would be diagnosed by a doctor on seeing a patient with thick and dry skin, puffy eyes and low metabolic rate?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Thyroid hormones are the body's metabolic engine. A lack of these hormones drastically slows down all cellular processes.
Solution:- Severe hypothyroidism in an adult is clinically termed Myxedema.
- Without thyroxine, the metabolic rate crashes. The body accumulates mucopolysaccharides under the skin, which trap water and create a distinct puffy appearance (especially around the eyes), accompanied by lethargy and dry skin.
Why other options are incorrect:Cretinism is hypothyroidism in
infants (causing dwarfism and retardation). Cushing's and Addison's relate to adrenal cortisol imbalances, not primary metabolic crash.
#6 of 44
NUMS 2024
Permalink
Choose the one NOT related to hyperparathyroidism:
View Answer & Propolis Autopsy
Correct Key: Option D
Diagnostic Explanation
Concept: Symptoms of parathyroid hormone dysfunction.
Solution: Hyperparathyroidism leads to hypercalcemia, muscle weakness, and kidney stones. Tetany is caused by hypocalcemia (hypoparathyroidism), making it unrelated to hyperparathyroidism.
#7 of 44
NUMS 2024
Permalink
A desert mammal faces severe dehydration in hot sunny day. Which internal condition would lead to secretion of ADH?
A
High osmotic pressure of blood
C
Low osmotic pressure of blood
D
Low solute potential of blood
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Osmotic pressure refers to how "salty" or concentrated a solution is. Water loss drives this pressure up.
Solution:- As the mammal sweats and exhales water vapor in the hot desert, it loses pure water from its plasma, leaving the salts behind.
- This thickens the blood, resulting in a dangerously high osmotic pressure. Osmoreceptors in the hypothalamus shrink in response to this hypertonic blood and fire signals to release ADH to save whatever water is left in the kidneys.
Why other options are incorrect:Dehydration causes
low blood pressure. Low osmotic pressure would mean the blood is too watery, which would inhibit ADH, not stimulate it.
#8 of 44
SZABMU 2024 Reconduct
Permalink
The neurosecretory cells are found in the:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The integration of the nervous system and the endocrine system occurs at a specific anatomical bridge in the brain.
Solution:- The hypothalamus bridges these systems using neurosecretory cells—specialized neurons that conduct action potentials but release hormones (like ADH, oxytocin, and releasing factors) into the blood instead of neurotransmitters into a synapse.
Why other options are incorrect:The pituitary gland is comprised of classical glandular tissue and axon terminals, but the actual cell bodies of the neurosecretory neurons reside firmly inside the hypothalamus.
#9 of 44
SZABMU 2024 Reconduct
Permalink
When a person intakes excess sugar diet his/her insulin level rises to:
A
Increase permeability of surface membrane
B
Increase blood glucose level
C
Deactivates enzymes in cells
D
Converts glycogen to glucose
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Glucose cannot passively diffuse into most mammalian cells; it requires a transport protein.
Solution:- A massive sugar spike triggers the pancreas to release large volumes of insulin.
- Insulin binds to tyrosine-kinase receptors on muscle and fat cells, signaling vesicles packed with GLUT4 transporter proteins to fuse with the cell membrane.
- This physically increases the permeability of the surface membrane to glucose, allowing it to rush out of the blood and into the cells for energy or storage.
Why other options are incorrect:Insulin decreases (not increases) blood glucose. It activates (not deactivates) glycogen synthesis enzymes, and it converts glucose to glycogen, not the reverse.
#10 of 44
SZABMU 2024 Reconduct
Permalink
Which body function is controlled through positive feedback mechanism?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Positive feedback systems are highly unstable and are only utilized when the body needs a rapid, explosive conclusion to a biological event.
Solution:- Labor contractions are driven by the hormone oxytocin. As the baby's head presses on the cervix, it sends nerve impulses to the brain to release oxytocin, which makes the uterus contract harder, pushing the baby further down, triggering even more oxytocin.
- This self-amplifying loop only terminates once the physical stretch is removed (i.e., the baby is born).
Why other options are incorrect:Every other biological variable listed (temperature, glucose, metabolic rate) must be strictly maintained at a constant level, which is exclusively achieved via negative feedback.
#11 of 44
SZABMU 2023
Permalink
Hormone released during child birth and in nursing women is:
View Answer & Propolis Autopsy
Correct Key: Option D
Diagnostic Explanation
Concept:A single hormone coordinates both the delivery of a newborn and its subsequent nourishment.
Solution:- Oxytocin is massively released during childbirth to force the uterus to contract.
- Immediately following birth, the same hormone is utilized during nursing to squeeze milk out of the alveolar ducts in the breast.
Why other options are incorrect:Progesterone levels actually plummet right before childbirth. Calcitonin is for bone mineralization.
#12 of 44
SZABMU 2023
Permalink
Which is not a function of testosterone?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Testosterone is a critical androgen responsible for male sexual development and continuous sperm generation.
Solution:- Testosterone works synergistically with FSH to actively promote and sustain high rates of sperm production (spermatogenesis).
- It does NOT limit spermatogenesis. High systemic levels of testosterone will inhibit pituitary LH via negative feedback, but locally in the testes, it is an absolute requirement for making sperm.
Why other options are incorrect:Because testosterone supports sperm production and negatively inhibits LH/FSH, options B, C, and D are true physiological functions, making A the false statement.
#13 of 44
ETEA 2023
Permalink
FSH stimulates spermatogenesis by stimulating ____ cells to complete the development of sperms.
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:In the testes, different pituitary hormones target very specific somatic cells to orchestrate reproduction.
Solution:- Follicle Stimulating Hormone (FSH) acts directly on the Sertoli cells (often called nurse cells) located inside the seminiferous tubules.
- Sertoli cells respond by producing androgen-binding protein (ABP) and providing the necessary nutrients and environment for spermatids to mature into fully developed spermatozoa.
Why other options are incorrect:LH targets Leydig cells to make testosterone. Inhibin is a hormone secreted
by Sertoli cells, not a cell type itself.
#14 of 44
NUMS 2023
Permalink
Hormone secreted in bulk due to decreased water content of blood is:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The body must continuously balance water intake and output. Dehydration shrinks blood volume and concentrates solutes.
Solution:- When blood water content drops, osmolarity rises. Hypothalamic osmoreceptors detect this thick, salty blood.
- They trigger the posterior pituitary to secrete bulk quantities of Antidiuretic Hormone (ADH). ADH forces the kidneys to reabsorb water, pulling it back into the blood to prevent fatal dehydration.
Why other options are incorrect:Glucagon and thyroxin deal with metabolic energy, not osmoregulation. Oxytocin is for reproduction.
#15 of 44
ETEA 2023
Permalink
The term polydipsia refers to:
A
A condition in which abnormally large volume of urine is produced
B
A condition of excessive thirst
C
condition of excessive hunger
D
A condition in which the concentration of blood decreases in the body
View Answer & Propolis Autopsy
Correct Key: Option B
Diagnostic Explanation
Concept:Medical terminology for diabetic symptoms relates to three classic "poly" signs: polyuria, polydipsia, and polyphagia.
Solution:- Due to massive fluid loss from frequent urination (polyuria), patients with uncontrolled diabetes become severely dehydrated.
- This dehydration triggers an unquenchable, relentless desire to drink water, a clinical symptom known as polydipsia (excessive thirst).
Why other options are incorrect:Large urine volume is polyuria. Excessive hunger is polyphagia.
#16 of 44
NUMS 2023
Permalink
Endorphins are produced in:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Endorphins are endogenous opioid neuropeptides that act as natural analgesics (painkillers).
Solution:- Endorphins are primarily synthesized and stored within the central nervous system, specifically in the pituitary gland and the hypothalamus of the brain.
- They are released in response to pain, stress, or intense physical exercise (causing "runner's high").
Why other options are incorrect:The adrenal gland handles adrenaline and cortisol. The thymus manages T-cell maturation, and the stomach secretes digestive juices.
#17 of 44
NUMS 2023
Permalink
The hormone responsible for production of sperm cells and male secondary sexual characteristics is:
View Answer & Propolis Autopsy
Correct Key: Option C
Diagnostic Explanation
Concept:Secondary sexual characteristics are the physical traits that distinguish biological males and females, manifesting at puberty.
Solution:- Testosterone, an androgen produced by the testes, drives the entire physical masculinization of the body.
- It not only ensures the continued production of sperm but also deepens the voice, increases muscle mass, and promotes facial and body hair growth.
Why other options are incorrect:Estrogen and progesterone dictate female reproductive cycles and characteristics.
#18 of 44
NUMS 2023
Permalink
Which hormone is chemically steroid?
View Answer & Propolis Autopsy
Correct Key: Option C
Diagnostic Explanation
Concept:Hormone chemical classification determines whether a hormone can pass through a lipid bilayer.
Solution:- Any hormone secreted by the adrenal cortex or the gonads is generally a steroid.
- Cortisone is a glucocorticoid produced by the adrenal cortex. Because it is synthesized from cholesterol, it is a lipid-soluble steroid hormone.
Why other options are incorrect:Insulin and ADH are water-soluble peptides. Thyroxin is an amine derived from tyrosine.
#19 of 44
UHS 2023
Permalink
Production of Follicle-stimulating hormone and Luteinizing hormone from the pituitary gland of female is controlled by:
View Answer & Propolis Autopsy
Correct Key: Option D
Diagnostic Explanation
Concept:The pituitary gland does not act autonomously; it requires clearance from a higher neural center to release its gonadotropins.
Solution:- The master controller of the reproductive axis is the hypothalamus.
- It secretes Gonadotropin-Releasing Hormone (GnRH) into the portal circulation, which directly commands the anterior pituitary to synthesize and release FSH and LH into the general bloodstream.
Why other options are incorrect:The ovary and stimulated follicles provide
feedback to the hypothalamus and pituitary, but the actual direct stimulatory control of pituitary output comes from the hypothalamus.
#20 of 44
SZABMU 2023
Permalink
Which body function is controlled through positive feed-back mechanism?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Positive feedback mechanisms are rare in biology because they rapidly drive physiological variables to extremes.
Solution:- Labor pains (contractions) represent one of the few essential positive feedback loops.
- The pain/stretch of the cervix causes a massive surge in oxytocin, which creates an even harder contraction, causing more stretch, more pain, and more oxytocin, ending only when the infant is expelled.
Why other options are incorrect:Body temperature and metabolic hormone levels (insulin, thyroxin) must be kept strictly stable via negative feedback.
#21 of 44
NUMS 2023
Permalink
Under activity of parathyroid glands causes a drop in blood of:
View Answer & Propolis Autopsy
Correct Key: Option D
Diagnostic Explanation
Concept:The four tiny parathyroid glands on the back of the thyroid are the body's primary calcium regulators.
Solution:- They secrete Parathyroid Hormone (PTH), which aggressively extracts calcium from the bones to raise blood calcium levels.
- If these glands are underactive (hypoparathyroidism), PTH is absent. The bones stop releasing calcium, and the kidneys excrete too much of it, resulting in a dangerous drop in blood calcium ions (\(Ca^{2+}\)).
Why other options are incorrect:Sodium and potassium balance are regulated by aldosterone from the adrenal glands, not the parathyroids.
#22 of 44
SZABMU 2023
Permalink
Follicle Stimulating hormones (FSH) is secreted by:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Tropic hormones are signaling molecules that target other endocrine glands rather than direct physiological tissues.
Solution:- FSH is a glycoprotein gonadotropin. It is synthesized by the gonadotropic cells situated in the anterior lobe of the pituitary gland.
- Once secreted, it travels to the gonads (ovaries or testes) to initiate gametogenesis.
Why other options are incorrect:The ovaries and testes are the targets of FSH, not the source. The adrenal gland handles stress and mineral balance.
#23 of 44
ETEA 2023
Permalink
Which of the following hormone is released by the posterior lobe of pituitary gland?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The posterior pituitary is essentially an extension of hypothalamic nervous tissue that stores two specific hormones.
Solution:- The only two hormones released by the posterior pituitary are oxytocin and Antidiuretic Hormone (ADH/Vasopressin).
Why other options are incorrect:Growth hormone and prolactin are synthesized in the anterior pituitary. Estrogen is produced by the ovaries.
#24 of 44
ETEA 2023
Permalink
The hormone "calcitonin" is secreted by:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept: Thyroid parafollicular cell endocrine output.
Solution: Calcitonin is synthesized and secreted by the parafollicular cells (C-cells) of the Thyroid gland to lower blood calcium levels.
#25 of 44
ETEA 2023 Retake
Permalink
In breast feeding mother, which hormone would be at an increased level?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Lactation requires sustained physiological changes to continuously produce nutrition for the newborn.
Solution:- Suckling by the infant strongly inhibits dopamine release from the hypothalamus, which removes the brakes on the anterior pituitary.
- This causes a massive and sustained increase in prolactin levels, which commands the mammary alveolar cells to continuously synthesize milk.
Why other options are incorrect:While oxytocin is also elevated for milk let-down, prolactin is the primary hormone driving the actual production process. Thyroxine, aldosterone, and insulin do not surge specifically for the mechanics of breastfeeding.
#26 of 44
SZABMU 2022
Permalink
Vasopressin is an example of:
View Answer & Propolis Autopsy
Correct Key: Option C
Diagnostic Explanation
Concept:Vasopressin, also known as Antidiuretic Hormone (ADH), regulates water reabsorption in the kidneys.
Solution:- Vasopressin is synthesized in the hypothalamus and consists of a short chain of exactly 9 amino acids.
- Because it is composed of a short amino acid chain, it is structurally classified as a peptide hormone.
Why other options are incorrect:It is not a steroid (which is lipid-based), not a catecholamine (like adrenaline), and not a glycoprotein (which would have attached carbohydrate chains like FSH).
#27 of 44
ETEA 2022
Permalink
Hormone are usually:
View Answer & Propolis Autopsy
Correct Key: Option C
Diagnostic Explanation
Concept:The endocrine system regulates the body through the secretion of highly specific molecules into the extracellular fluid.
Solution:- Hormones act as chemical messengers that travel through the bloodstream to bind to specific receptors on distant target cells, eliciting a physiological response.
Why other options are incorrect:Biological catalysts are enzymes, which speed up biochemical reactions but do not act as long-distance communicators. Hormones are chemical, not physical or strictly genetic messengers.
#28 of 44
SZABMU 2022
Permalink
Posterior lobe of pituitary gland produces:
B
Thyroid stimulating hormone
C
Adrenocorticotrophic hormone
D
Follicle stimulating hormone
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The posterior lobe of the pituitary gland (neurohypophysis) does not synthesize its own hormones but stores and releases hormones produced by the hypothalamus.
Solution:- The two hormones released by the posterior pituitary are Antidiuretic Hormone (ADH) and Oxytocin.
Why other options are incorrect:TSH, ACTH, and FSH are all tropic hormones synthesized and secreted directly by the
anterior lobe of the pituitary gland.
#29 of 44
SZABMU 2022
Permalink
Tetany is caused by _ in blood.
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Calcium ions stabilize voltage-gated sodium channels in resting neurons. Proper calcium homeostasis is heavily regulated by the parathyroid gland.
Solution:- When parathyroid hormone (PTH) levels drop, it leads to severe hypocalcemia (low blood calcium).
- Without enough extracellular calcium, sodium channels become overly permeable, causing neurons to depolarize spontaneously. This results in continuous, involuntary muscle spasms known as tetany.
Why other options are incorrect:High calcium (hypercalcemia) causes sluggish reflexes and muscle weakness, not spasms. Magnesium imbalances also cause issues but are not the primary driver of classical tetany.
#30 of 44
ETEA 2022
Permalink
Which of the following lobes of the pituitary gland is known as master gland of the body?
D
Anterio-posterial gland
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The pituitary gland is historically called the "master gland" because it exerts hierarchical control over many other endocrine structures.
Solution:- Specifically, the anterior lobe (adenohypophysis) secretes numerous tropic hormones (TSH, ACTH, FSH, LH) that dictate the functions of the thyroid, adrenal cortex, and gonads.
Why other options are incorrect:The posterior lobe only releases ADH and oxytocin. The intermediate lobe primarily secretes MSH in some species and is not considered the main orchestrator.
#31 of 44
BUMHS 2022
Permalink
Acromegaly is caused due to over secretion of:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Somatotropic Hormone (STH), also known as Growth Hormone (GH), stimulates protein synthesis and bone growth.
Solution:- If there is hypersecretion of STH after the epiphyseal plates of long bones have closed (i.e., in adulthood), the bones can no longer lengthen.
- Instead, bones in the hands, feet, jaw, and face become abnormally thick, a condition clinically termed acromegaly.
Why other options are incorrect:Over-secretion of TSH causes hyperthyroidism. ICSH and FSH affect the gonads, not systemic skeletal thickening.
#32 of 44
DUHS 2022
Permalink
It has neurosecretory cells that secrete releasing and inhibiting hormone:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The neuroendocrine system connects neural activity directly to endocrine output.
Solution:- The hypothalamus contains highly specialized neurons called neurosecretory cells.
- These cells synthesize releasing hormones (like TRH, CRH) and inhibiting hormones (like somatostatin) that travel via the hypophyseal portal system to regulate the anterior pituitary gland.
Why other options are incorrect:The pituitary gland responds to these releasing factors but does not produce them. The thyroid and adrenal glands are purely classical endocrine targets.
#33 of 44
PMC 2020
Permalink
Which of the following neurotransmitters function, both as neurotransmitter and hormones, decreasing our perception of pain?
View Answer & Propolis Autopsy
Correct Key: Option D
Diagnostic Explanation
Concept:Certain molecules in the body serve dual roles, acting locally across synapses as neurotransmitters and systemically via blood as hormones.
Solution:- Endorphins are endogenous opioid peptides produced mainly in the central nervous system and the pituitary gland.
- They bind to opiate receptors to naturally inhibit the transmission of pain signals and induce feelings of euphoria.
Why other options are incorrect:Epinephrine is a stress hormone, dopamine is involved in reward pathways, and serotonin regulates mood. While they act as dual messengers, they are not primarily responsible for systemic pain reduction like endorphins.
#34 of 44
PMC 2020
Permalink
Which body function is controlled through positive feedback mechanism?
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:A positive feedback loop amplifies the initial stimulus, pushing the physiological process further away from its starting state to achieve a definitive endpoint.
Solution:- During childbirth, the baby's head pushes against the cervix. Stretch receptors signal the hypothalamus to release oxytocin.
- Oxytocin causes the uterus to contract violently, which pushes the baby harder against the cervix, triggering the release of even more oxytocin. This explosive cascade of labor contractions continues until the baby is delivered.
Why other options are incorrect:Insulin, body temperature, and thyroxin release are all strictly regulated by negative feedback loops to maintain a steady baseline.
#35 of 44
ETEA 2019
Permalink
Chemically hormones are:
D
Both Proteins and Steroids
View Answer & Propolis Autopsy
Correct Key: Option D
Diagnostic Explanation
Concept:Hormones are organic chemical messengers secreted by endocrine glands directly into the bloodstream to regulate specific target organs.
Solution:- Hormones have diverse chemical structures but are generally classified into three main categories: peptides/proteins (e.g., insulin, glucagon), steroids (e.g., estrogen, testosterone), and amino acid derivatives (e.g., epinephrine).
- Therefore, hormones are chemically proteins and steroids.
Why other options are incorrect:Carbohydrates (like glucose or glycogen) serve as primary energy sources or structural components, not as long-distance endocrine signaling molecules.
#36 of 44
AJK 2019
Permalink
When secretion of ADH is increased, the amount of water reabsorbed is:
D
Has no effect on reabsorption
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Antidiuretic Hormone (ADH) maintains blood osmolarity by preventing excessive water loss in the urine.
Solution:- ADH binds to receptors on the collecting ducts of the nephrons in the kidney.
- This triggers the insertion of aquaporin water channels into the cell membrane, which drastically increases the reabsorption of free water back into the bloodstream, producing highly concentrated urine.
Why other options are incorrect:Decreased water reabsorption occurs when ADH levels drop, leading to dilute urine (as seen in diabetes insipidus).
#37 of 44
ETEA 2019
Permalink
In male luteinizing hormone is also known as:
View Answer & Propolis Autopsy
Correct Key: Option B
Diagnostic Explanation
Concept:Hormones often have alternative names based on their specific physiological target in males versus females.
Solution:- In females, LH triggers ovulation and luteinization.
- In males, the exact same molecule targets the interstitial cells (Leydig cells) in the testes to stimulate testosterone production. Hence, it is biologically referred to as Interstitial Cell Stimulating Hormone (ICSH).
Why other options are incorrect:ACTH targets the adrenal cortex. TRF (Thyrotropin-Releasing Factor) is from the hypothalamus. MSH affects melanocytes.
#38 of 44
ETEA 2019
Permalink
The deficiency of which micro-nutrient causes goiter formation?
View Answer & Propolis Autopsy
Correct Key: Option C
Diagnostic Explanation
Concept:The thyroid gland relies heavily on specific trace minerals to construct its active hormones.
Solution:- Thyroxine (\(T_4\)) and Triiodothyronine (\(T_3\)) absolutely require iodine molecules to be synthesized.
- Without sufficient dietary iodine, \(T_3\) and \(T_4\) levels fall, removing negative feedback on the pituitary. The pituitary furiously pumps out TSH, which overstimulates the thyroid gland, causing it to swell immensely into a condition known as a goiter.
Why other options are incorrect:Iron deficiency causes anemia. Zinc is important for immunity, and sodium is for nerve impulses.
#39 of 44
ETEA 2019
Permalink
A man has to face interview, but during his first five minutes before the interview he experiences sweating, increased heart rate and respiration. Which hormone is responsible for his restlessness?
A
Epinephrine and nor-epinephrine
C
Adrenocorticotropic hormone
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The "fight-or-flight" response prepares the body for sudden stress by rapidly altering cardiovascular and respiratory rates.
Solution:- In acutely stressful situations (like a high-stakes interview), the sympathetic nervous system stimulates the adrenal medulla.
- The adrenal medulla instantly dumps epinephrine (adrenaline) and norepinephrine into the bloodstream, which collectively cause pupil dilation, sweating, tachycardia (increased heart rate), and hyperventilation.
Why other options are incorrect:Aldosterone regulates sodium/water balance over hours. Insulin/glucagon regulate glucose slowly. ACTH simply tells the adrenal cortex to release cortisol, which is for long-term stress, not acute panic.
#40 of 44
NTS 2018
Permalink
Pituitary gland releases hormone and hormone while ovaries produce _ and progesterone.
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The reproductive cycle is driven by the Hypothalamic-Pituitary-Gonadal (HPG) axis.
Solution:- The anterior pituitary synthesizes and releases the gonadotropins: Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH).
- In response to FSH and LH, the maturing follicles and corpus luteum in the ovaries produce the steroid hormones estrogen and progesterone.
Why other options are incorrect:Options B, C, and D misplace estrogen as a pituitary hormone or incorrectly order the gonadal vs pituitary output.
#41 of 44
MDCAT 2016
Permalink
____ hormone is antagonistic to insulin and causes increase in blood glucose level.
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:Homeostasis requires opposing pairs of hormones (antagonists) to keep blood levels within a narrow, healthy range.
Solution:- While insulin drastically forces glucose out of the blood and into cells, its direct antagonist is glucagon.
- Glucagon ensures that during fasting or exercise, the liver breaks down glycogen reserves to maintain an adequate supply of blood glucose for the brain.
Why other options are incorrect:Calcitonin regulates calcium. While thyroxin and norepinephrine influence metabolism and can mobilize energy, glucagon is the primary, direct antagonist to insulin in maintaining standard glucose homeostasis.
#42 of 44
MDCAT 2015
Permalink
\(\alpha\)-cells of pancreas secrete a hormone known as:
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The endocrine portion of the pancreas contains distinct cell types that secrete opposing metabolic hormones.
Solution:- Alpha (\(\alpha\)) cells continuously monitor blood glucose and secrete glucagon when blood sugar drops too low.
- Glucagon travels to the liver and stimulates glycogenolysis, dumping stored glucose back into the blood.
Why other options are incorrect:Beta cells secrete insulin. Gastrin is secreted by the stomach lining, and rennin is an enzyme in the stomachs of infants to curdle milk.
#43 of 44
LUMHS 2014
Permalink
[LUMMHC-2014] Destruction of all beta cells in the pancreas would cause:
A
Insulin secretion to stop and an increase in blood glucose
B
Glucagon secretion to stop and a decrease in blood glucose
C
Glucagon secretion to stop and an increase in blood glucose
D
Insulin secretion to stop and a decrease in blood glucose
View Answer & Propolis Autopsy
Correct Key: Option A
Diagnostic Explanation
Concept:The Islets of Langerhans in the pancreas contain beta cells, which are exclusively responsible for insulin production.
Solution:- Insulin is the only hormone capable of lowering blood glucose by facilitating its uptake into skeletal muscle and adipose tissue.
- If all beta cells are destroyed (as occurs in autoimmune Type 1 Diabetes Mellitus), insulin secretion stops completely. Consequently, glucose becomes trapped in the bloodstream, leading to a massive increase in blood glucose.
Why other options are incorrect:Alpha cells produce glucagon, so their destruction would affect glucagon, not beta cell destruction.
#44 of 44
MDCAT 2014
Permalink
Which one of the following is a steroid hormone?
View Answer & Propolis Autopsy
Correct Key: Option D
Diagnostic Explanation
Concept:Steroid hormones are structurally derived from the lipid precursor cholesterol and can easily cross cell membranes.
Solution:- The five major classes of steroid hormones are glucocorticoids, mineralocorticoids, androgens, progestogens, and estrogens.
- Therefore, estrogen is a classical steroid hormone produced primarily by the ovaries.
Why other options are incorrect:Glucagon is a polypeptide. Epinephrine and thyroxin are both derived from the amino acid tyrosine, not cholesterol.
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