Question 1

The sleep-wake cycle of human body is regulated by the ____ hormone.?

Accepted Answer

Answer reason: Melatonin, produced primarily by the pineal gland, is the key hormone regulating the circadian (sleep–wake) cycle. Its secretion increases in darkness and decreases with light exposure, helping promote sleep onset and synchronize the body’s internal clock. Cortisol follows a diurnal rhythm but primarily supports wakefulness and stress responses rather than being the main sleep-regulating hormone. Prolactin and progesterone have other primary reproductive/metabolic roles and are not the principal circadian regulators.

Question 2

Which hormone responsible for milk production?

Accepted Answer

Answer reason: Prolactin, secreted by the anterior pituitary, is the primary hormone that stimulates milk synthesis in the mammary glands (lactogenesis). Oxytocin mainly causes milk ejection (let-down) by contracting myoepithelial cells rather than producing milk. Estrogen supports breast development during pregnancy but suppresses active milk secretion until after delivery. Cortisol has supportive metabolic roles but is not the primary driver of milk production.

Question 3

Hormone is important for fight and flight response.?

Accepted Answer

Answer reason: The fight-or-flight response is mediated by sympathetic nervous system activation, with the adrenal medulla releasing adrenaline (epinephrine). Adrenaline increases heart rate, blood pressure, bronchodilation, and mobilizes glucose to rapidly supply energy for acute stress. Insulin lowers blood glucose, oxytocin is involved in uterine contraction and lactation, and melatonin regulates sleep-wake cycles, so they are not primary fight-or-flight hormones.

Question 4

Which electrolyte imbalance is commonly associated with adrenal insufficiency (Addison's disease)?

Accepted Answer

Answer reason: In primary adrenal insufficiency, low aldosterone reduces renal sodium reabsorption and potassium excretion, leading to hyperkalemia (often with hyponatremia). The impaired mineralocorticoid effect decreases urinary K+ secretion in the distal nephron. Therefore hyperkalemia is a hallmark electrolyte abnormality in Addison’s disease, making it the best choice among the options.

Question 5

Happy hormones are?

Accepted Answer

Answer reason: Oxytocin is commonly referred to as a “happy” or “bonding” hormone because it is released during social connection, touch, childbirth, and breastfeeding and promotes attachment and positive affect. Dopamine is also linked to pleasure and reward, but the question asks for a single best “happy hormone,” and oxytocin is the most specifically associated with wellbeing through bonding. Cortisone is a glucocorticoid related to stress and inflammation, not a “happy hormone.” Therefore, oxytocin is the best answer among the options.

Question 6

Gigantism is the result of over secretion of ______ Hormone?

Accepted Answer

Answer reason: Gigantism is caused by excess secretion of growth hormone (GH), typically from a pituitary adenoma, occurring before epiphyseal plate closure in childhood/adolescence. Elevated GH increases IGF-1 production (mainly in the liver), driving linear bone growth and overall tissue growth. The other listed hormones (FSH, ACTH, GnRH) regulate gonadal function or adrenal cortisol production and do not primarily cause generalized linear overgrowth.

Question 7

Alpha cells of pancreas secrete —

Accepted Answer

Answer reason: Pancreatic alpha cells (in the islets of Langerhans) secrete glucagon, which raises blood glucose primarily by stimulating hepatic glycogenolysis and gluconeogenesis. In contrast, beta cells secrete insulin to lower blood glucose. Cortisol is produced by the adrenal cortex and thyroxine (T4) by the thyroid gland, making them incorrect for pancreatic alpha cells.

Question 8

Osteomalacia in adults is due to deficiency of?

Accepted Answer

Answer reason: Osteomalacia is defective mineralization of osteoid in adults, most commonly due to vitamin D deficiency. Vitamin D is required for intestinal absorption of calcium and phosphate; deficiency leads to low mineral availability and soft, weak bones. Calcium deficiency alone can contribute, but the classic primary cause tested for osteomalacia is vitamin D deficiency. Vitamin C deficiency causes scurvy, and iron deficiency causes anemia, not osteomalacia.

Question 9

Prolactin is mainly responsible for?

Accepted Answer

Answer reason: Prolactin, released from the anterior pituitary, primarily stimulates milk synthesis (lactogenesis) in the mammary glands. In contrast, oxytocin is responsible for milk ejection (let-down) and also causes uterine contractions. Ovulation is mainly regulated by the LH surge from the anterior pituitary (with FSH supporting follicular development). Therefore, the best answer is milk production.

Question 10

A patient complains of constantly craving salt, low blood pressure, and unexplained darkened areas and spots on their skin. Which disease do these things MOST likely indicate?

Accepted Answer

Answer reason: Salt craving and low blood pressure suggest mineralocorticoid (aldosterone) deficiency causing renal sodium wasting and volume depletion, which is classic for primary adrenal insufficiency (Addison's disease). Hyperpigmentation occurs due to elevated ACTH (and related melanocyte-stimulating activity) in primary adrenal failure. Diabetes insipidus causes polyuria/polydipsia rather than hyperpigmentation, and Cushing syndrome typically causes hypertension and features of cortisol excess rather than hypotension and salt craving.

Question 11

Which of the following is NOT a symptom of diabetes mellitus?

Accepted Answer

Answer reason: Classic symptoms of diabetes mellitus include the “3 Ps”: polydipsia (excessive thirst), polyuria (frequent urination), and polyphagia (increased appetite), driven by hyperglycemia and osmotic diuresis with cellular energy deficit. Hypertension is not a typical presenting symptom; rather, it is a common comorbidity/risk factor in people with diabetes and may develop over time due to insulin resistance, obesity, and vascular changes. Therefore, hypertension is the option that is NOT a symptom of diabetes mellitus.

Question 12

Goitre is the deficiency of?

Accepted Answer

Answer reason: Goitre is an enlargement of the thyroid gland, most classically due to iodine deficiency. Iodine is required for synthesis of thyroid hormones (T3 and T4); when iodine is low, thyroid hormone production drops. This triggers increased TSH secretion from the pituitary, stimulating thyroid hypertrophy and hyperplasia, producing goitre. Calcium, vitamin D, and iron deficiencies are associated with other conditions (e.g., rickets/osteomalacia, anemia) rather than primary goitre formation.

Question 13

Which of the following hormones is produced by the pancreas, and what is its primary function in the body?

Accepted Answer

Answer reason: Insulin is produced by the beta cells of the pancreatic islets (islets of Langerhans). Its primary function is to lower blood glucose by promoting glucose uptake into cells (especially muscle and adipose) and stimulating glycogen synthesis in the liver and muscle. In contrast, glucagon raises blood glucose, and estrogen/testosterone are primarily produced by the ovaries/testes (and adrenal sources), not the pancreas.

Question 14

Which organ controls blood glucose levels?

Accepted Answer

Answer reason: Among the listed organs, the liver is central to maintaining blood glucose by storing glucose as glycogen (glycogenesis) after meals and releasing glucose via glycogenolysis and gluconeogenesis during fasting. These processes are regulated primarily by insulin and glucagon but are carried out largely by hepatic metabolism. The heart and lungs do not regulate blood glucose homeostasis, and while the kidney can contribute to gluconeogenesis and glucose reabsorption, it is not the primary controller compared with the liver in this option set.

Question 15

Main hormone of pregnancy:

Accepted Answer

Answer reason: Progesterone is considered the main hormone of pregnancy because it prepares and maintains the endometrium for implantation and supports continuation of pregnancy by reducing uterine contractility. Early in pregnancy it is produced by the corpus luteum and later predominantly by the placenta. Estrogen rises during pregnancy as well, but its primary roles are uterine growth and breast development rather than maintaining gestation. Insulin and thyroxine are important metabolic hormones but are not the primary hormones responsible for sustaining pregnancy.

Question 16

Stress indicating hormones are__________?

Accepted Answer

Answer reason: Cortisol is the primary glucocorticoid released from the adrenal cortex in response to stress via activation of the hypothalamic-pituitary-adrenal (HPA) axis, making it a classic “stress hormone” and a common biomarker of physiologic stress. Although adrenaline (epinephrine) rises rapidly during acute sympathetic activation, it is a catecholamine rather than the main hormonal indicator commonly referenced in endocrine stress responses. ACTH is a pituitary trophic hormone that stimulates cortisol release, but cortisol is the downstream effector typically measured to indicate stress response.

Question 17

Woman after head injury, having serum osmolarity of 175 mOsm/L and urine osmolarity of 1200 mOsm/L. Most likely diagnosis is which of the following?

Accepted Answer

Answer reason: A very low serum osmolality (175 mOsm/L) with an inappropriately high urine osmolality (1200 mOsm/L) indicates excess ADH effect causing water retention and concentrated urine. Head injury is a classic trigger for SIADH due to hypothalamic/pituitary dysregulation. In diabetes insipidus (central or nephrogenic), urine is dilute (low urine osmolality) and serum osmolality tends to be elevated. Pure water deprivation typically raises serum osmolality and concentrates urine, which does not match the markedly low serum osmolality here.

Question 18

Normal Fasting Blood Sugar Level is ??

Accepted Answer

Answer reason: Normal fasting plasma glucose in nonpregnant adults is typically about 70–99 mg/dL, with many nursing references rounding this to 70–100 mg/dL. Values from 100–125 mg/dL indicate impaired fasting glucose (prediabetes), and ≥126 mg/dL on repeat testing supports diabetes. Therefore, 70–100 mg/dL is the best match among the options for a normal fasting blood sugar range.

Question 19

Which hormone is called the “Love hormone”?

Accepted Answer

Answer reason: Oxytocin is commonly referred to as the “love hormone” because it is strongly involved in social bonding, trust, and attachment behaviors. It is released during intimate contact, childbirth, and breastfeeding, supporting pair bonding and maternal-infant bonding. Dopamine and serotonin are neurotransmitters linked to reward and mood, while adrenaline mediates the fight-or-flight stress response rather than bonding.

Question 20

The Pancreas secretes?

Accepted Answer

Answer reason: The pancreas has an endocrine function via the islets of Langerhans, which secrete hormones directly into the bloodstream. Beta cells specifically produce insulin, which lowers blood glucose by promoting cellular uptake and storage of glucose. Peptic juice is secreted by the stomach, and bile is produced by the liver (stored in the gallbladder), not the pancreas.

Question 21

Testosterone hormone is also called...?

Accepted Answer

Answer reason: Testosterone is the primary male sex hormone and is classified as an androgen, a group of hormones responsible for development and maintenance of male secondary sexual characteristics. Estrogen and progesterone are primarily considered female sex hormones, with different dominant physiologic roles. Therefore, the best match for what testosterone is also called is androgen.

Question 22

Blood sugar regulated by:

Accepted Answer

Answer reason: Insulin is the primary hormone that regulates blood glucose by facilitating cellular uptake of glucose (especially in muscle and adipose tissue) and promoting glycogen synthesis in the liver. When insulin levels are low or insulin action is impaired, blood glucose rises (hyperglycemia), as seen in diabetes mellitus. Cortisol can increase glucose via gluconeogenesis, but it is not the main regulator in normal physiology. Thyroxine and estrogen do not directly regulate blood sugar as the primary control hormone.

Question 23

Beta cells of pancreas secrete —

Accepted Answer

Answer reason: Pancreatic beta (β) cells in the islets of Langerhans secrete insulin, the hormone responsible for lowering blood glucose by promoting cellular uptake and glycogen synthesis. In contrast, alpha (α) cells secrete glucagon, which raises blood glucose. Cortisol is produced by the adrenal cortex (zona fasciculata), and aldosterone by the adrenal cortex (zona glomerulosa), not the pancreas.

Question 24

Which hormone is responsible for Acne?

Accepted Answer

Answer reason: Acne is strongly influenced by androgens, especially testosterone (and its more potent metabolite dihydrotestosterone), which increase sebaceous gland size and sebum production. Increased sebum and follicular hyperkeratinization promote comedone formation and create an environment for Cutibacterium acnes proliferation and inflammation. Estrogen generally counteracts androgen effects on sebaceous glands, and thyroid hormones and gonadotropins are not the primary direct drivers of acne lesions.

Question 25

Which hormone is primarily responsible for the induction of ovulation in the female reproductive cycle?

Accepted Answer

Answer reason: Ovulation is triggered by the mid-cycle surge of luteinizing hormone (LH), which causes rupture of the dominant ovarian follicle and release of the oocyte. Estrogen rises during the follicular phase and helps create the positive feedback that leads to the LH surge, but it is not the direct inducer of ovulation. FSH primarily stimulates follicular growth and maturation, while progesterone mainly supports the luteal phase and endometrial maintenance after ovulation.

Question 26

Which organ produces insulin?

Accepted Answer

Answer reason: Insulin is produced by the beta cells in the islets of Langerhans within the pancreas. It is secreted in response to elevated blood glucose and promotes cellular glucose uptake and storage (glycogenesis and lipogenesis). The liver is a major target of insulin and helps store glucose, but it does not produce insulin. Kidneys and spleen also do not produce insulin.

Question 27

The disease characterized by the inability to produce insulin is?

Accepted Answer

Answer reason: Diabetes mellitus is characterized by impaired insulin secretion and/or insulin action; in type 1 diabetes mellitus there is autoimmune destruction of pancreatic beta cells leading to an inability to produce insulin. Diabetes insipidus involves deficiency or resistance to antidiuretic hormone (ADH), not insulin. Addison’s disease is adrenal cortical insufficiency (low cortisol/aldosterone), and Cushing’s syndrome is excess cortisol, neither defined by lack of insulin production.

Question 28

Which of the following hormones is secreted by the anterior pituitary?

Accepted Answer

Answer reason: The anterior pituitary (adenohypophysis) secretes trophic hormones including TSH, ACTH, GH, prolactin, FSH, and LH. ADH is released from the posterior pituitary (synthesized in the hypothalamus). Insulin is produced by pancreatic beta cells, and epinephrine is secreted by the adrenal medulla. Therefore, TSH is the only anterior pituitary hormone listed.

Question 29

Simmonds Disease is?

Accepted Answer

Answer reason: Simmonds disease refers to severe anterior pituitary insufficiency, historically described as pituitary cachexia. It results from hypopituitarism with deficiency of multiple pituitary hormones (e.g., ACTH, TSH, gonadotropins), leading to systemic endocrine failure. Therefore, the most accurate option is hypopituitarism rather than primary thyroid disorders or hyperpituitarism.

Question 30

Which Hormone causes Gluconeogenesis?

Accepted Answer

Answer reason: Gluconeogenesis is primarily stimulated by counter-regulatory hormones, especially glucagon (in the liver via increased cAMP) and cortisol (by upregulating gluconeogenic enzymes and mobilizing amino acids). Insulin inhibits gluconeogenesis by promoting glucose uptake and glycogen synthesis and suppressing hepatic glucose output. Epinephrine can contribute indirectly, but glucagon and cortisol are the clearest and most directly tested drivers. Therefore the best answer is the combined option: cortisol plus glucagon.

Question 31

Q.3 The type II diabetes mellitus commonly affects......

Accepted Answer

Answer reason: Type 2 diabetes mellitus classically has an adult onset and is most commonly diagnosed in people over age 30 due to progressive insulin resistance and beta-cell dysfunction over time. Although it is now increasingly seen in younger adults and adolescents, the typical demographic in standard teaching remains older than 30. The other options better fit type 1 diabetes (younger onset) or represent complications/comorbidities rather than the most common affected age group.

Question 32

The islets of Langerhans contain –

Accepted Answer

Answer reason: Islets of Langerhans are the endocrine portion of the pancreas and are composed of multiple hormone-secreting cell types. The major ones are alpha cells (secrete glucagon) and beta cells (secrete insulin), which regulate blood glucose homeostasis. Acinar and duct cells belong to the exocrine pancreas, producing digestive enzymes and transporting secretions, respectively. RBCs and WBCs are blood cells and are not specific constituents of pancreatic islets.

Question 33

The hormone responsible for “stress alert” is –?

Accepted Answer

Answer reason: “Stress alert” refers to the immediate fight-or-flight response mediated by the sympathetic nervous system and the adrenal medulla. Adrenaline (epinephrine) is rapidly released and increases heart rate, blood pressure, bronchodilation, and glucose availability for quick action. Cortisol is also a stress hormone but primarily supports longer-term metabolic adaptation rather than the immediate alert response. Oxytocin and prolactin are not responsible for stress alert physiology.

Question 34

Which hormone is primarily responsible for maintaining vaginal epithelium and pH?

Accepted Answer

Answer reason: Estrogen maintains the thickness and maturation of the vaginal epithelium and increases glycogen content in epithelial cells. Lactobacilli metabolize glycogen to lactic acid, which helps maintain the normal acidic vaginal pH. With low estrogen (e.g., menopause), the epithelium becomes atrophic and vaginal pH rises. Progesterone, testosterone, and FSH are not the primary hormones responsible for vaginal epithelial maintenance and baseline pH.

Question 35

Which hormone helps in childbirth?

Accepted Answer

Answer reason: Oxytocin stimulates rhythmic uterine smooth muscle contractions during labor and also promotes milk ejection postpartum. Clinically, synthetic oxytocin is used to induce or augment labor because it increases the frequency and strength of uterine contractions. Insulin primarily regulates blood glucose, cortisol is a stress hormone involved in metabolism and inflammation, and thyroxine regulates basal metabolic rate—none directly drive uterine contractions for childbirth.

Question 36

Which protein is detected in pregnancy test kits?

Accepted Answer

Answer reason: Pregnancy test kits detect human chorionic gonadotropin (hCG), a hormone produced by the syncytiotrophoblast of the developing placenta shortly after implantation. hCG rises rapidly in early pregnancy and is measurable in urine and blood, making it an ideal marker for test kits. FSH and LH are pituitary gonadotropins and are not the target analytes for pregnancy tests. TSH is a thyroid hormone regulator and is unrelated to pregnancy test detection.

Question 37

Which is a principal male of sex hormone?

Accepted Answer

Answer reason: Testosterone is the principal male sex hormone produced primarily by the testes (Leydig cells) under LH stimulation. It is responsible for development of male secondary sexual characteristics and supports spermatogenesis (along with FSH acting on Sertoli cells). FSH is a gonadotropin that regulates gamete production but is not the primary male sex steroid. Prolactin and progesterone are not principal male sex hormones.

Question 38

Diabetes mellitus is due to deficiency of?

Accepted Answer

Answer reason: Diabetes mellitus is characterized by hyperglycemia due to inadequate insulin action. In type 1 diabetes, there is absolute insulin deficiency from autoimmune destruction of pancreatic beta cells; in type 2, there is relative insulin deficiency with insulin resistance. Deficiency of glucagon would tend to cause hypoglycemia, while cortisol and adrenaline are counter-regulatory hormones that increase blood glucose rather than being deficient in diabetes.

Question 39

Which hormone regulates blood calcium level?

Accepted Answer

Answer reason: Parathyroid hormone (PTH) is the primary regulator of serum calcium, released in response to low blood calcium. It raises calcium levels by stimulating bone resorption, increasing renal calcium reabsorption, and promoting activation of vitamin D to increase intestinal calcium absorption. Insulin regulates glucose, thyroxine regulates basal metabolic rate, and estrogen affects bone metabolism but is not the main acute regulator of serum calcium.

Question 40

Which hormone is detected in urine for pregnancy test?

Accepted Answer

Answer reason: Urine pregnancy tests detect human chorionic gonadotropin (hCG), a hormone produced by the trophoblast/placenta shortly after implantation. hCG rises rapidly in early pregnancy and is filtered into urine, making it a reliable biomarker for detection. LH, progesterone, and prolactin are involved in reproductive physiology but are not the target analytes for standard urine pregnancy tests.

Question 41

MOST COMMON CAUSE OF CUSHING'S SYNDROME

Accepted Answer

Answer reason: The most common cause of Cushing syndrome overall is exogenous (iatrogenic) glucocorticoid exposure from chronic steroid therapy (e.g., prednisone). This is more common than endogenous causes such as pituitary ACTH-secreting adenoma (Cushing disease), adrenal adenoma/carcinoma, or ectopic ACTH production. Long-term steroid use suppresses the HPA axis and leads to hypercortisolism features despite low endogenous ACTH/cortisol production.

Question 42

Which hormone is detected in pregnancy tests?

Accepted Answer

Answer reason: Pregnancy tests detect human chorionic gonadotropin (hCG), a hormone produced by trophoblastic cells of the developing placenta shortly after implantation. hCG rises rapidly in early pregnancy and is measurable in urine and blood, making it a reliable marker for pregnancy detection. Estrogen and progesterone increase during pregnancy but are not the target hormones for standard pregnancy tests. Oxytocin is primarily involved in labor and lactation rather than early pregnancy detection.

Question 43

Oxytocin is secreted from?

Accepted Answer

Answer reason: Oxytocin is synthesized in the hypothalamus (paraventricular and supraoptic nuclei) and then transported down axons to the posterior pituitary, where it is stored and released into the bloodstream. Therefore, the site from which it is secreted (released) is the posterior pituitary (neurohypophysis). The anterior pituitary secretes hormones like prolactin, GH, TSH, ACTH, LH, and FSH, while the adrenal cortex secretes steroid hormones such as cortisol and aldosterone.

Question 44

The condition caused by underactive adrenal cortex is —?

Accepted Answer

Answer reason: An underactive adrenal cortex causes primary adrenal insufficiency, known as Addison’s disease, due to deficient cortisol (and often aldosterone) production. This leads to findings such as hypotension, weight loss, fatigue, hyponatremia, and hyperkalemia. In contrast, Cushing’s syndrome is due to excess glucocorticoids, goitre is thyroid enlargement, and gigantism is caused by excess growth hormone.

Question 45

The presence of glucose in urine indicates:

Accepted Answer

Answer reason: Glucose appears in urine (glycosuria) when blood glucose rises above the renal threshold, overwhelming proximal tubular reabsorption. This is classically seen in diabetes mellitus due to hyperglycemia from insulin deficiency or resistance. While some renal tubular disorders can cause glycosuria with normal serum glucose, the best single answer among the options is diabetes mellitus. Kidney failure more typically causes reduced urine output and retention of wastes rather than isolated glycosuria.

Question 46

Which of these hormones will the body secrete when you encounter a snake?

Accepted Answer

Answer reason: Encountering a snake is an acute stressor that activates the sympathetic nervous system and adrenal medulla, triggering release of adrenaline (epinephrine). Adrenaline mediates the “fight-or-flight” response by increasing heart rate, blood pressure, bronchodilation, and blood glucose availability. Insulin is generally suppressed during acute stress, oxytocin is primarily involved in labor/lactation and bonding, and thyroxine regulates baseline metabolic rate rather than immediate stress responses.

Question 47

What is the main function of the pancreas?

Accepted Answer

Answer reason: The pancreas has both exocrine and endocrine functions, but its key endocrine role is regulating blood glucose via hormone secretion. The islets of Langerhans secrete insulin, which lowers blood glucose by promoting cellular uptake and storage. While the pancreas also produces digestive enzymes (exocrine function), the best single answer among the options is insulin production.

Question 48

Which vitamin is essential for the absorption of calcium in the intestine?

Accepted Answer

Answer reason: Vitamin D (via its active form, calcitriol) increases intestinal absorption of calcium by upregulating calcium transport proteins in the gut. Without adequate vitamin D, dietary calcium absorption decreases, which can contribute to hypocalcemia and impaired bone mineralization (e.g., rickets/osteomalacia). The other listed vitamins do not play the primary regulatory role in intestinal calcium absorption.

Question 49

What is Thyroxine?

Accepted Answer

Answer reason: Thyroxine (T4) is a thyroid hormone produced by the thyroid gland’s follicular cells and released into the bloodstream. It is an iodinated amino acid derivative that is converted peripherally to the more active triiodothyronine (T3). Thyroid hormones regulate basal metabolic rate, thermogenesis, growth, and development. Therefore, it is classified as a hormone rather than a protein, enzyme, or vitamin.

Question 50

Which hormone is most associated with the appearance of Linea nigra?

Accepted Answer

Answer reason: Linea nigra is a hyperpigmented line that commonly appears in pregnancy due to increased melanogenesis. Elevated melanocyte-stimulating hormone (MSH), along with other pregnancy-related hormonal changes, stimulates melanocytes to produce more melanin. This increased melanin deposition causes darkening in areas such as the linea alba, leading to the linea nigra. Estrogen and progesterone are associated with pregnancy changes but are less directly responsible for this pigmentation than MSH.

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