Have ducts and pour their secretions into blood directly

Have ducts which straightway pour secretions into target organs

CHEMICAL COORDINATION AND INTEGRATION MCQs for NEET UG BIOLOGY — Easy, Page 5

121 Easy

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Presence of glycosuria and ketonuria conditions in urine are indicative of which disorder?

View answer and explanation

Correct option: D

Diabetes mellitus

Option D (Diabetes mellitus) is correct because glycosuria and ketonuria are indicative of this disorder.

Solution approach

Correct Answer + Core Reason: Diabetes mellitus. Glycosuria and ketonuria are characteristic signs of this metabolic disorder.

Step-by-Step Solution:

Step 1: Recall the symptoms associated with diabetes mellitus.

Step 2: Glycosuria (glucose in urine) occurs because the kidneys cannot reabsorb all the excess glucose in the blood.

Step 3: Ketonuria (ketones in urine) occurs because the body is breaking down fat for energy due to insufficient glucose utilization.

Step 4: The presence of both glycosuria and ketonuria strongly suggests diabetes mellitus.

Why other options are wrong:
- Option A: Diabetes insipidus is related to ADH and water balance, not glucose or ketones.
- Option B: Renal calculi are kidney stones, not directly related to glucose or ketone levels in urine.
- Option C: Glomerulonephritis is a kidney disease, not directly related to glucose or ketone levels in urine.

Key Concepts:
- Diabetes mellitus
- Glycosuria
- Ketonuria

Memory Aids:
- Diabetes mellitus = Sugar and ketones in urine.

Quick Tips:
- Remember the specific symptoms associated with each disorder.

122 Easy

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I. Increase of heart beat,  II. Increase of respiration rate,  III. Stimulate breakdown of glycogen, .  IV. Stimulate breakdown of lipid and protein.  Statement written above are the features of which hormone

View answer and explanation

Correct option: D

Catecholamine

Option D (Catecholamine) is correct because the listed effects are characteristic of catecholamines like epinephrine and norepinephrine.

Solution approach

Correct Answer + Core Reason: Catecholamine. Catecholamines are known to increase heart rate, respiration rate, stimulate glycogen breakdown, and stimulate lipid and protein breakdown.

Step-by-Step Solution:

Step 1: Analyze each statement and determine which hormone exhibits these effects.

Step 2: I. Increase of heart beat: Catecholamines (epinephrine and norepinephrine) increase heart rate.

Step 3: II. Increase of respiration rate: Catecholamines increase respiration rate.

Step 4: III. Stimulate breakdown of glycogen: Catecholamines stimulate glycogenolysis (breakdown of glycogen).

Step 5: IV. Stimulate breakdown of lipid and protein: Catecholamines stimulate lipolysis (breakdown of lipids) and can influence protein metabolism.

Step 6: PTH (Parathyroid hormone) primarily regulates calcium levels.

Step 7: TCT (Thyrocalcitonin or Calcitonin) lowers blood calcium levels.

Step 8: Thymosin is involved in T-cell maturation.

Final Answer: Catecholamine.

Why other options are wrong:
- Option A (PTH): PTH primarily regulates calcium levels, not the listed effects.
- Option B (TCT): TCT lowers blood calcium levels and does not have the listed effects.
- Option C (Thymosin): Thymosin is involved in T-cell maturation, not the listed effects.
- Option D (Catecholamine): This is the correct answer as explained above.

Key Concepts:
- Catecholamines (epinephrine, norepinephrine) effects
- PTH function
- Calcitonin function
- Thymosin function

Memory Aids:
- Catecholamines: "Fight or Flight" response (increases heart rate, respiration, energy mobilization)

Quick Tips:
- Remember the primary functions of each hormone to quickly eliminate incorrect options.

123 Easy

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Study the following statements:
a) Both MSH and melatonin influences the pigmentation.
b) Thymosins help in differentiation of T lymphocytes and promote production of antibodies.
c) Erythropoiesis is influenced by erythropoietin and thyroxin.
d) Parathyroid hormone promotes ossification of bone by increasing blood calcium levels.
The correct ones of the above are

View answer and explanation

Correct option: B

Only a, b and c

Option B (Only a, b and c) is correct because statements a, b, and c are accurate descriptions of hormone functions.

Solution approach

Correct Answer + Core Reason: Only a, b and c. These statements accurately describe hormonal functions.

Step-by-Step Solution:

Step 1: Evaluate each statement.

Step 2: MSH and melatonin influence pigmentation (correct).

Step 3: Thymosins help in T lymphocyte differentiation and antibody production (correct).

Step 4: Erythropoiesis is influenced by erythropoietin and thyroxin (correct).

Step 5: Parathyroid hormone promotes bone resorption, not ossification, by increasing blood calcium levels (incorrect).

Why other options are wrong:
- Option A: Statement d is incorrect.
- Option C: Statement d is incorrect.
- Option D: Statements c is correct, but d is incorrect.

Key Concepts:
- MSH and melatonin
- Thymosins
- Erythropoiesis
- Parathyroid hormone

Memory Aids:
- PTH = increases blood calcium = bone resorption

Quick Tips:
- Know the specific functions of different hormones.

124 Easy

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Large number of hormones are secreted by

View answer and explanation

Correct option: A

Pituitary

Option A (Pituitary) is correct because the pituitary gland secretes a large number of hormones that regulate various bodily functions.

Solution approach

Correct Answer + Core Reason: Pituitary. The pituitary gland secretes a large number of hormones.

Step-by-Step Solution:

Step 1: Consider the hormone secretion of each gland.

Step 2: Pituitary gland: Secretes hormones like growth hormone (GH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin, and others.

Step 3: Thyroid gland: Primarily secretes thyroxine (T4) and triiodothyronine (T3).

Step 4: Hypothalamus: Secretes releasing and inhibiting hormones that control the pituitary gland.

Step 5: Adrenal gland: Secretes hormones like cortisol, aldosterone, and adrenaline.

Step 6: The pituitary gland secretes the largest number of hormones compared to the other options.

Why other options are wrong:
- Option B: The thyroid gland mainly secretes T3 and T4.
- Option C: The hypothalamus controls the pituitary but doesn't directly secrete as many hormones.
- Option D: The adrenal gland secretes hormones related to stress and electrolyte balance, but fewer in number than the pituitary.

Key Concepts:
- Pituitary hormone secretion
- Endocrine gland functions

Memory Aids:
- Pituitary = Master gland (controls many other glands).

Quick Tips:
- Know the major hormones secreted by each endocrine gland.

125 Easy

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The function of oxytocin is to help in

View answer and explanation

Correct option: A

Child birth

The correct answer is Child birth because oxytocin stimulates uterine contractions during labor.

Solution approach

Correct Answer + Core Reason: Child birth. Oxytocin helps in childbirth by stimulating uterine contractions.

Step-by-Step Solution:

Step 1: Recall the functions of oxytocin.

Step 2: Oxytocin is a hormone that stimulates uterine contractions during labor and milk ejection from the mammary glands after childbirth.

Step 3: Gametogenesis is the process of producing gametes (sperm and eggs) and is not directly influenced by oxytocin.

Step 4: Growth is primarily regulated by growth hormone.

Step 5: Lactation refers to milk production, while oxytocin is responsible for milk ejection.

Why other options are wrong:
- Option B: Gametogenesis is not directly related to oxytocin function.
- Option C: Growth is primarily regulated by growth hormone, not oxytocin.
- Option D: Oxytocin is responsible for milk ejection, not milk production (lactation).

Key Concepts:
- Oxytocin function
- Uterine contractions
- Milk ejection

Memory Aids:
- Oxytocin = Contractions and Milk Ejection

Quick Tips:
- Remember the two main functions of oxytocin: uterine contractions and milk ejection.

126 Easy

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Thymosin hormone is secreted by

View answer and explanation

Correct option: C

Thymus gland

Option C (Thymus gland) is correct because thymosin is a hormone secreted by the thymus gland and is involved in the development of T-lymphocytes.

Solution approach

Correct Answer + Core Reason: Thymus gland. Thymosin is secreted by the thymus.

Step-by-Step Solution:

Step 1: Recall the hormones secreted by the thymus gland.

Step 2: The thymus gland secretes thymosins.

Step 3: Thymosins are involved in the differentiation and maturation of T-lymphocytes.

Why other options are wrong:
- Option A: Thyroid gland: The thyroid gland secretes thyroxine, triiodothyronine, and calcitonin.
- Option B: Parathyroid gland: The parathyroid gland secretes parathyroid hormone (PTH).
- Option D: Hypothalamus: The hypothalamus secretes releasing and inhibiting hormones that regulate the pituitary gland.

Key Concepts:
- Thymus gland
- Thymosins
- T-lymphocytes

Memory Aids:
- Thymus = Thymosins

Quick Tips:
- Know which hormones are secreted by which glands.

127 Easy

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Select the incorrect match w.r.t. hormone, its source gland and function.

View answer and explanation

Correct option: B

Hormone – Thymosin, Source – Thyroid gland, Function – Regulates basal metabolic rate

Option B (Hormone – Thymosin, Source – Thyroid gland, Function – Regulates basal metabolic rate) is the incorrect match because thymosin is secreted by the thymus gland, not the thyroid gland, and it is involved in T-lymphocyte maturation, not regulating basal metabolic rate.

Solution approach

Correct Answer + Core Reason: Hormone – Thymosin, Source – Thyroid gland, Function – Regulates basal metabolic rate. Thymosin is secreted by the thymus gland, not the thyroid gland.

Step-by-Step Solution:

Step 1: Analyze each option to identify the source gland and function of the hormone.

Step 2: Option A is correct: Melatonin is secreted by the pineal gland and regulates diurnal rhythm.

Step 3: Option B is incorrect: Thymosin is secreted by the thymus gland and plays a role in the maturation of T-lymphocytes. The thyroid gland secretes thyroxine and triiodothyronine, which regulate basal metabolic rate.

Step 4: Option C is correct: Insulin is secreted by the pancreas and regulates blood glucose levels.

Step 5: Option D is correct: CCK is secreted by the gastrointestinal tract and stimulates the secretion of pancreatic enzymes and the release of bile juice from the gallbladder.

Why other options are wrong:
- Option A: Melatonin is indeed produced by the pineal gland and regulates diurnal rhythm.
- Option C: Insulin is indeed produced by the pancreas and regulates blood glucose level.
- Option D: CCK is indeed produced by the gastro-intestinal tract and stimulates secretion of pancreatic enzymes and release of bile juice from gall bladder.

Key Concepts:
- Endocrine glands and their hormones
- Functions of thymosin, melatonin, insulin, and CCK
- Regulation of basal metabolic rate

Memory Aids:
- Thymus = Thymosin, T-cells
- Pancreas = Insulin
- Pineal = Melatonin

Quick Tips:
- Know the source and function of major hormones to identify incorrect matches quickly.

128 Easy

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Which of the following hormones have the direct effect on BP (Blood Pressure)? I. Thymosin,  II. PRL,  III. MSH,  IV. Adrenaline,  V. Non-adrenaline.  Select the option containing the correct pair

View answer and explanation

Correct option: C

IV and V

Option C (IV and V) is correct because adrenaline and noradrenaline directly affect blood pressure by influencing heart rate and vasoconstriction.

Solution approach

Correct Answer + Core Reason: IV and V. Adrenaline and non-adrenaline (norepinephrine) directly affect blood pressure.

Step-by-Step Solution:

Step 1: Analyze the effect of each hormone on blood pressure.

Step 2: I. Thymosin: Thymosin is involved in T-cell maturation and does not directly affect blood pressure.

Step 3: II. PRL (Prolactin): Prolactin is involved in milk production and does not directly affect blood pressure.

Step 4: III. MSH (Melanocyte-Stimulating Hormone): MSH affects skin pigmentation and does not directly affect blood pressure.

Step 5: IV. Adrenaline (Epinephrine): Adrenaline increases heart rate and causes vasoconstriction, leading to an increase in blood pressure.

Step 6: V. Non-adrenaline (Norepinephrine): Norepinephrine causes vasoconstriction, leading to an increase in blood pressure.

Final Answer: IV and V.

Why other options are wrong:
- Option A (I and II): Thymosin and Prolactin do not directly affect blood pressure.
- Option B (III and IV): MSH does not directly affect blood pressure, although adrenaline does.
- Option C (IV and V): This is the correct answer as explained above.
- Option D (I and IV): Thymosin does not directly affect blood pressure, although adrenaline does.

Key Concepts:
- Adrenaline (epinephrine) and norepinephrine effects on blood pressure
- Thymosin function
- Prolactin function
- MSH function

Memory Aids:
- Adrenaline/Norepinephrine: "Fight or Flight" response (increases blood pressure)

Quick Tips:
- Remember the primary functions of each hormone and their effects on the cardiovascular system.

129 Easy

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Endocrine glands are

View answer and explanation

Correct option: A

Ductless glands whose secretions pour directly into blood

The correct answer is A (Ductless glands whose secretions pour directly into blood) because endocrine glands are defined by their lack of ducts and direct secretion into the bloodstream.

Solution approach

Correct Answer + Core Reason: Ductless glands whose secretions pour directly into blood. Endocrine glands release hormones directly into the bloodstream.

Step-by-Step Solution:

Step 1: Define endocrine glands. Endocrine glands are ductless glands that secrete hormones directly into the bloodstream.

Step 2: Evaluate option A: Ductless glands whose secretions pour directly into blood. This aligns with the definition of endocrine glands.

Step 3: Evaluate option B: Have ducts and pour their secretions into blood directly. This contradicts the definition of endocrine glands, which are ductless.

Step 4: Evaluate option C: Have ducts which straightway pour secretions into target organs. This describes exocrine glands, not endocrine glands.

Step 5: Evaluate option D: All of the above. Since options B and C are incorrect, this option is also incorrect.

Why other options are wrong:
- Option B: Incorrect because endocrine glands do not have ducts.
- Option C: Incorrect because this describes exocrine glands, not endocrine glands.
- Option D: Incorrect because options B and C are incorrect.

Key Concepts:
- Endocrine glands
- Exocrine glands
- Hormone secretion

Memory Aids:
- ENDO = Inside (secrete internally into blood)
- EXO = Outside (secrete externally through ducts)

Quick Tips:
- Differentiate between endocrine and exocrine glands based on the presence or absence of ducts.

130 Easy

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Which one of the following hormone is a modified amino acid?

View answer and explanation

Correct option: A

Epinephrine

Option A is correct because epinephrine (adrenaline) is derived from the amino acid tyrosine.

Solution approach

Correct Answer + Core Reason: A. Epinephrine. Epinephrine is a modified amino acid (tyrosine derivative).

Step-by-Step Solution:

Step 1: Recall the different types of hormones and their chemical structures.

Step 2: Epinephrine (adrenaline) is a catecholamine, which is derived from the amino acid tyrosine.

Step 3: Progesterone and oestrogen are steroid hormones derived from cholesterol.

Step 4: Prostaglandins are lipid-based hormones derived from arachidonic acid.

Why other options are wrong:
- Option B: Progesterone is a steroid hormone.
- Option C: Prostaglandin is a lipid-derived hormone.
- Option D: Oestrogen is a steroid hormone.

Key Concepts:
- Hormone classification
- Amino acid-derived hormones
- Steroid hormones
- Lipid-derived hormones

Memory Aids:
- Epinephrine: Amino acid derivative
- Steroid hormones: Cholesterol backbone

Quick Tips:
- Remember the basic chemical structures of different hormone types.

131 Easy

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Pair of ovary located …… of female (human)

View answer and explanation

Correct option: B

Inside the abdomen

Option B (Inside the abdomen) is correct because the ovaries are located within the abdominal cavity in human females.

Solution approach

Correct Answer + Core Reason: Inside the abdomen. The ovaries are located within the abdominal cavity.

Step-by-Step Solution:

Step 1: Identify the location of the ovaries in the female reproductive system.

Step 2: The ovaries are female gonads responsible for producing eggs (ova) and hormones like estrogen and progesterone.

Step 3: In human females, the ovaries are located inside the abdominal cavity, on either side of the uterus.

Why other options are wrong:
- Option A: The ovaries are not located outside the abdomen.
- Option C: The scrotal sac is a structure in males that houses the testes, not the ovaries.
- Option D: The inguinal canal is a passage in the abdominal wall, but the ovaries are not located inside it.

Key Concepts:
- Ovaries location
- Female reproductive system
- Abdominal cavity

Memory Aids:
- Think of the ovaries as being "in-side" the body, specifically the abdomen.

Quick Tips:
- Remember that the ovaries are internal organs located within the abdominal cavity.

132 Easy

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The hormone that increases the blood calcium level and decreases its excretion by kidney is

View answer and explanation

Correct option: A

Parathormone

Option A (Parathormone) is correct because parathormone increases blood calcium levels and decreases calcium excretion by the kidneys.

Solution approach

Correct Answer + Core Reason: Parathormone. Parathormone increases blood calcium levels and reduces its excretion by the kidneys.

Step-by-Step Solution:

Step 1: Analyze the question: The question asks for the hormone that increases blood calcium and decreases its excretion by the kidneys.

Step 2: Consider the options:
- Parathormone: increases blood calcium levels by stimulating bone resorption, increasing calcium absorption in the intestines, and decreasing calcium excretion by the kidneys.
- Calcitonin: decreases blood calcium levels.
- Thyroxine: regulates metabolism but does not directly affect calcium levels.
- Insulin: regulates blood glucose levels, not calcium levels.

Step 3: Conclusion: Parathormone is the correct answer.

Why other options are wrong:
- Option B: Calcitonin decreases blood calcium levels.
- Option C: Thyroxine primarily regulates metabolism.
- Option D: Insulin primarily regulates blood glucose levels.

Key Concepts:
- Parathormone (PTH)
- Calcitonin
- Calcium regulation

Memory Aids:
- PTH: Pulls calcium from bone into blood.

Quick Tips:
- Remember the roles of PTH and calcitonin in calcium homeostasis.

133 Easy

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Selective destruction of the zona glomeruiosa of the adrenal cortex would cause a deficiency of which hormone?

View answer and explanation

Correct option: A

Aldosterone

Option A (Aldosterone) is correct because the zona glomerulosa is the primary site of aldosterone production in the adrenal cortex.

Solution approach

Correct Answer + Core Reason: Aldosterone. The zona glomerulosa of the adrenal cortex is responsible for the production of aldosterone.

Step-by-Step Solution:

Step 1: Recall the zones of the adrenal cortex and the hormones they produce.

Step 2: The adrenal cortex has three zones: zona glomerulosa, zona fasciculata, and zona reticularis.

Step 3: Zona glomerulosa produces mineralocorticoids, primarily aldosterone, which regulates sodium and potassium balance.

Step 4: Zona fasciculata produces glucocorticoids, primarily cortisol, which regulates glucose metabolism and stress response.

Step 5: Zona reticularis produces androgens, such as androstenedione and dehydroepiandrosterone (DHEA), which are sex hormones.

Step 6: Selective destruction of the zona glomerulosa would directly impair aldosterone production.

Final Answer: Aldosterone.

Why other options are wrong:
- Option A (Aldosterone): This is the correct answer as explained above.
- Option B (Androstenedione): Androstenedione is produced primarily in the zona reticularis.
- Option C (Cortisol): Cortisol is produced primarily in the zona fasciculata.
- Option D (Dehydroepiandrosterone): Dehydroepiandrosterone is produced primarily in the zona reticularis.

Key Concepts:
- Adrenal cortex structure and function
- Zona glomerulosa: Aldosterone
- Zona fasciculata: Cortisol
- Zona reticularis: Androgens

Memory Aids:
- GFR (Glomerulosa, Fasciculata, Reticularis) - Salt, Sugar, Sex (Mineralocorticoids, Glucocorticoids, Gonadocorticoids)

Quick Tips:
- Remember the layers of the adrenal cortex and the hormones they produce.

134 Easy

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Accumulation and release centre of pituitary gland hormones is

View answer and explanation

Correct option: C

Hypothalamus

The correct answer is Hypothalamus because it synthesizes and releases hormones that control the pituitary gland's hormone release.

Solution approach

Correct Answer + Core Reason: Hypothalamus. The hypothalamus is the accumulation and release center of pituitary gland hormones.

Step-by-Step Solution:

Step 1: Recall the relationship between the hypothalamus and the pituitary gland.

Step 2: The hypothalamus produces releasing and inhibiting hormones that travel to the anterior pituitary (adenohypophysis) via the hypophyseal portal system.

Step 3: These hormones regulate the release of hormones from the adenohypophysis.

Step 4: The hypothalamus also produces ADH and oxytocin, which are transported to and stored in the posterior pituitary (neurohypophysis) for later release.

Why other options are wrong:
- Option A: Neurohypophysis stores and releases hormones synthesized in the hypothalamus, but it doesn't synthesize them.
- Option B: Adenohypophysis produces its own hormones in response to hypothalamic releasing and inhibiting hormones.
- Option D: Pars distalis is a part of the adenohypophysis and produces hormones, but it is not the accumulation and release center of pituitary gland hormones.

Key Concepts:
- Hypothalamus-pituitary axis
- Releasing and inhibiting hormones
- Neurohypophysis
- Adenohypophysis

Memory Aids:
- Hypothalamus = Control Center

Quick Tips:
- Understand the difference between the anterior and posterior pituitary and their respective hormone regulation.

135 Easy

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Which of the following statements is correct regarding hypothalamic control of pituitary function?

View answer and explanation

Correct option: A

All the hypothalamic hormones are synthesized and secreted by neurons

The correct answer is A (All the hypothalamic hormones are synthesized and secreted by neurons) because hypothalamic hormones are neurohormones.

Solution approach

Correct Answer + Core Reason: All the hypothalamic hormones are synthesized and secreted by neurons. Hypothalamic hormones are neurohormones, synthesized and secreted by neurons in the hypothalamus.

Step-by-Step Solution:

Step 1: Recall the nature of hypothalamic hormones.

Step 2: Hypothalamic hormones are synthesized and secreted by specialized neurons in the hypothalamus.

Step 3: These hormones then regulate the anterior pituitary function.

Why other options are wrong:
- Option B: Blood flows from the hypothalamus to the anterior pituitary in the portal vessels, not the other way around.
- Option C: Hypothalamic releasing hormones are secreted into the hypophyseal portal system, not the general circulation in significant amounts.
- Option D: Loss of dopaminergic neurons in the hypothalamus would lead to an increase in prolactin secretion, not a fall, as dopamine inhibits prolactin secretion.

Key Concepts:
- Hypothalamic-pituitary axis
- Neurohormones
- Hypophyseal portal system

Memory Aids:
- Hypothalamus controls pituitary; Neurons secrete hormones

Quick Tips:
- Remember the direction of blood flow in the hypophyseal portal system.

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GIP (Gastric Inhibitory Peptide)

View answer and explanation

Correct option: A

Inhibits the gastric secretion and motility

Option A (Inhibits the gastric secretion and motility) is correct because GIP (Gastric Inhibitory Peptide) reduces gastric acid secretion and slows down gastric emptying.

Solution approach

Correct Answer + Core Reason: Inhibits the gastric secretion and motility. GIP inhibits both gastric secretion and motility.

Step-by-Step Solution:

Step 1: GIP (Gastric Inhibitory Peptide), also known as glucose-dependent insulinotropic peptide, is a hormone secreted by the K cells of the duodenum and jejunum.

Step 2: GIP primarily functions to inhibit gastric acid secretion and reduce gastric motility.

Step 3: It also stimulates insulin release from pancreatic beta cells in response to elevated blood glucose levels.

Why other options are wrong:
- Option B: GIP inhibits both gastric secretion and motility, not just secretion.
- Option C: GIP inhibits, not activates, gastric secretion and motility.
- Option D: GIP inhibits, not activates, gastric secretion.

Key Concepts:
- GIP (Gastric Inhibitory Peptide)
- Gastric secretion
- Gastric motility
- Insulin release

Memory Aids:
- GIP \"G\"astric \"I\"nhibitory \"P\"eptide inhibits gastric function.

Quick Tips:
- Know the functions of major gastrointestinal hormones.

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Major roles of thymus gland in humans is/are

View answer and explanation

Correct option: D

Both (a) and ©

The correct answer is D (Both (a) and (c)) because the thymus gland is responsible for the differentiation of T-lymphocytes and promotes the production of antibodies.

Solution approach

Correct Answer + Core Reason: Both (a) and (c). The thymus gland differentiates T-lymphocytes and influences antibody production.

Step-by-Step Solution:

Step 1: Recall the function of the thymus gland: The thymus gland is the primary site for T-lymphocyte maturation and differentiation. T-lymphocytes are crucial for cell-mediated immunity.

Step 2: Understand the role of T-lymphocytes in antibody production: While B-lymphocytes are the primary cells responsible for antibody production, T-helper cells (a type of T-lymphocyte) play a crucial role in activating B-lymphocytes to produce antibodies.

Step 3: Identify the major roles of the thymus gland: The thymus gland is involved in the differentiation of T-lymphocytes and indirectly promotes the production of antibodies by activating B-lymphocytes.

Why other options are wrong:
- Option A: Differentiation of T-lymphocytes is a major role of the thymus gland, but it's not the only one.
- Option B: Differentiation of B-lymphocytes primarily occurs in the bone marrow, not the thymus gland.
- Option C: Promote production of antibodies is indirectly influenced by the thymus through T-helper cells, but it's not the only role.

Key Concepts:
- Thymus gland
- T-lymphocytes
- B-lymphocytes
- Antibody production
- Cell-mediated immunity

Memory Aids:
- Think of "Thymus" and "T-cells" being important for cell-mediated immunity, and T-helper cells help B-cells make antibodies.

Quick Tips:
- Remember that the thymus gland is crucial for T-lymphocyte maturation and indirectly influences antibody production.

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Each receptor is …A… to one hormone only and hence, receptors are …B… . Hormone receptor complex formation leads to certain biochemical changes in the …C… . Choose the option containing correct combination of A, B and C

View answer and explanation

Correct option: B

A-specific, B-specific, C-target tissue

Option B (A-specific, B-specific, C-target tissue) is correct because each receptor is specific to one hormone, and the hormone-receptor complex affects the target tissue.

Solution approach

Correct Answer + Core Reason: A-specific, B-specific, C-target tissue. Hormones bind specifically to their receptors in target tissues.

Step-by-Step Solution:

Step 1: Hormones exhibit specificity, meaning each hormone binds to a specific receptor.

Step 2: Receptors are also specific, meaning each receptor binds to only one hormone.

Step 3: The hormone-receptor complex formation triggers biochemical changes in the target tissue, leading to a physiological response.

Why other options are wrong:
- Option A: Receptors are specific, not non-specific.
- Option C: Hormones and receptors are both specific, not non-specific.
- Option D: Hormones and receptors are both specific, not non-specific.

Key Concepts:
- Hormone specificity
- Receptor specificity
- Target tissue

Memory Aids:
- Specificity is key to hormone action.

Quick Tips:
- Remember that hormones and receptors have a lock-and-key relationship.

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Gluconeogenesis, lipolysis and proteolysis processes are stimulated by

View answer and explanation

Correct option: A

Glucocorticoids

Option A is correct because glucocorticoids, such as cortisol, stimulate gluconeogenesis, lipolysis, and proteolysis to increase blood glucose levels.

Solution approach

Correct Answer + Core Reason: A. Glucocorticoids. Glucocorticoids stimulate gluconeogenesis, lipolysis, and proteolysis.

Step-by-Step Solution:

Step 1: Recall the functions of glucocorticoids and mineralocorticoids.

Step 2: Glucocorticoids (e.g., cortisol) promote gluconeogenesis (glucose production from non-carbohydrate sources), lipolysis (breakdown of fats), and proteolysis (breakdown of proteins).

Step 3: Mineralocorticoids (e.g., aldosterone) regulate electrolyte balance.

Why other options are wrong:
- Option B: Mineralocorticoids primarily regulate electrolyte balance, not gluconeogenesis, lipolysis, and proteolysis.
- Option C: Mineralocorticoids do not have a significant role in gluconeogenesis, lipolysis, and proteolysis.
- Option D: Glucocorticoids do stimulate these processes.

Key Concepts:
- Glucocorticoid function
- Mineralocorticoid function
- Gluconeogenesis
- Lipolysis
- Proteolysis

Memory Aids:
- Glucocorticoids: Affect glucose, lipids, and proteins.

Quick Tips:
- Remember the specific metabolic effects of glucocorticoids.

140 Easy

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Which of the following is the correct function of endocrine system with reference to chemical coordination?

View answer and explanation

Correct option: B

Provides chemical integration through hormones

Option B (Provides chemical integration through hormones) is correct because the endocrine system uses hormones for chemical coordination.

Solution approach

Correct Answer + Core Reason: Provides chemical integration through hormones. The endocrine system uses hormones to coordinate bodily functions through chemical signals.

Step-by-Step Solution:

Step 1: Define the function of the endocrine system.

Step 2: Hormones are chemical messengers that integrate bodily functions.

Step 3: The endocrine system provides chemical, not neural, integration.

Why other options are wrong:
- Option A: The nervous system provides neural integration, not the endocrine system.
- Option C: The nervous system provides point-to-point connections for quick coordination.
- Option D: The endocrine system provides chemical integration.

Key Concepts:
- Endocrine system
- Chemical coordination
- Hormones

Memory Aids:
- Endocrine = chemical

Quick Tips:
- Differentiate between neural and chemical coordination.

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Understanding +4 | -1

The activity of formation of milk is regulated by the activity of …A… . While the ejection of milk is controlled by …B… hormone
Here, A and B refers to

View answer and explanation

Correct option: B

A-prolactin; A-oxytocin

Option B (A-prolactin; A-oxytocin) is correct because prolactin stimulates milk production, while oxytocin stimulates milk ejection.

Solution approach

Correct Answer + Core Reason: A-prolactin; A-oxytocin. Prolactin stimulates milk production, and oxytocin stimulates milk ejection.

Step-by-Step Solution:

Step 1: Recall the functions of prolactin and oxytocin.

Step 2: Prolactin: Stimulates milk production in the mammary glands.

Step 3: Oxytocin: Stimulates the contraction of myoepithelial cells around the mammary glands, causing milk ejection.

Step 4: Therefore, the activity of milk formation is regulated by prolactin, and the ejection of milk is controlled by oxytocin.

Why other options are wrong:
- Option A: This option reverses the roles of prolactin and oxytocin.
- Option C: Both milk formation and ejection are not controlled by prolactin alone.
- Option D: This option reverses the roles of prolactin and oxytocin.

Key Concepts:
- Prolactin function
- Oxytocin function
- Lactation

Memory Aids:
- Pro-lactin = Pro-duction of milk.
- Oxy-tocin = Ejection (think \"toes in\" for contraction and ejection).

Quick Tips:
- Remember the distinct roles of prolactin and oxytocin in lactation.

142 Easy

142 of 149

Analyzing +4 | -1

Select the mismatch among the following w.r.t. disorders associated with endocrine glands.

View answer and explanation

Correct option: A

Addison's disease - Underproduction of hormones by adrenal medulla

Option A (Addison's disease - Underproduction of hormones by adrenal medulla) is the mismatch because Addison's disease involves the adrenal cortex, not the medulla.

Solution approach

Correct Answer + Core Reason: Addison's disease - Underproduction of hormones by adrenal medulla. Addison's disease is associated with the adrenal cortex, not the medulla.

Step-by-Step Solution:
Step 1: Identify the endocrine glands and their associated disorders.
Step 2: Recall that Addison's disease is caused by hyposecretion of hormones from the adrenal cortex (glucocorticoids and mineralocorticoids).
Step 3: The adrenal medulla secretes epinephrine and norepinephrine.
Step 4: Therefore, Addison's disease is incorrectly matched with the adrenal medulla.

Why other options are wrong:
- Option B: Cretinism - Hypothyroidism is a correct match because cretinism results from hypothyroidism in children.
- Option C: Acromegaly - Excessive secretion of GH in adults is a correct match because acromegaly is caused by excessive growth hormone secretion in adults.
- Option D: Graves' disease - Hyperthyroidism is a correct match because Graves' disease is a form of hyperthyroidism.

Key Concepts:
- Endocrine glands and their hormones
- Disorders associated with endocrine glands
- Adrenal cortex vs. adrenal medulla

Memory Aids:
- Cortex = Cortisol (Addison's affects the cortex)

Quick Tips:
- Remember the specific hormones produced by each part of the adrenal gland (cortex vs. medulla).

143 Easy

143 of 149

Remembering +4 | -1

Which of the following hormones is not a secretary product of human placenta?

View answer and explanation

Correct option: B

Prolactin

Option B (Prolactin) is correct because prolactin is primarily secreted by the anterior pituitary gland, not the placenta.

Solution approach

Correct Answer + Core Reason: Prolactin. Prolactin is secreted by the anterior pituitary gland, not the placenta.

Step-by-Step Solution:

Step 1: Identify the hormones secreted by the human placenta.

Step 2: The human placenta secretes several hormones essential for maintaining pregnancy.

Step 3: These hormones include human chorionic gonadotropin (hCG), estrogen, and progesterone.

Step 4: Prolactin is secreted by the anterior pituitary gland and is involved in milk production.

Why other options are wrong:
- Option A: Human chorionic gonadotropin (hCG) is secreted by the placenta to maintain the corpus luteum during early pregnancy.
- Option C: Estrogen is secreted by the placenta to support the development of the fetus and maternal tissues.
- Option D: Progesterone is secreted by the placenta to maintain the uterine lining and prevent uterine contractions.

Key Concepts:
- Placental hormones
- Human chorionic gonadotropin (hCG)
- Estrogen
- Progesterone
- Prolactin

Memory Aids:
- Remember that the placenta secretes hormones that start with "H" like hCG and hPL (human placental lactogen), as well as estrogen and progesterone.

Quick Tips:
- Know the major hormones secreted by the placenta and their functions.

144 Easy

144 of 149

Analyzing +4 | -1

Which of the following statements are not associated with the pituitary gland?
(A) Pars nervosa is also known as posterior pituitary
(B) Pars distalis produces 6 hormones
(C ) Oxytocin/ADH is actually synthesised by the pars inter media
(D) Oxytocin/ADH are transported axonally to pars distalis

View answer and explanation

Correct option: B

C and D

Option B (C and D) is correct because Oxytocin/ADH are synthesized in the hypothalamus and transported axonally to the pars nervosa (posterior pituitary), not the pars intermedia or pars distalis.

Solution approach

Correct Answer + Core Reason: C and D. Oxytocin/ADH are synthesized in the hypothalamus, not the pars intermedia, and are transported axonally to the pars nervosa, not the pars distalis.

Step-by-Step Solution:

Step 1: Evaluate statement (A): Pars nervosa is also known as posterior pituitary.

Step 2: This statement is correct. The pars nervosa is indeed the posterior pituitary.

Step 3: Evaluate statement (B): Pars distalis produces 6 hormones.

Step 4: This statement is correct. The pars distalis (anterior pituitary) produces 6 major hormones: GH, PRL, TSH, ACTH, FSH, and LH.

Step 5: Evaluate statement (C ): Oxytocin/ADH is actually synthesised by the pars inter media.

Step 6: This statement is incorrect. Oxytocin and ADH are synthesized in the hypothalamus, not the pars intermedia.

Step 7: Evaluate statement (D) Oxytocin/ADH are transported axonally to pars distalis.

Step 8: This statement is incorrect. Oxytocin and ADH are transported axonally to the pars nervosa (posterior pituitary), not the pars distalis (anterior pituitary).

Why other options are wrong:
- Option A: Statements A and D, A is correct, D is incorrect.
- Option C: Statements B and C, B is correct, C is incorrect.
- Option D: Statements A and B, both are correct.

Key Concepts:
- Pituitary gland structure and function
- Pars nervosa (posterior pituitary)
- Pars distalis (anterior pituitary)
- Oxytocin and ADH synthesis and transport

Memory Aids:
- Posterior Pituitary: Stores and Releases (hormones made in the hypothalamus)

Quick Tips:
- Remember the difference between the anterior and posterior pituitary and the hormones they produce or release.

145 Easy

145 of 149

Remembering +4 | -1

The thymus gland is a lobular structure located on the …A… side of the …B… and aorta. The thymus plays a significant role in the development …C… system
Choose the correct combination of A, B and C

View answer and explanation

Correct option: C

A-dorsal, B-heart, C-immune

Option A-ventral, B-heart, C-immune is correct because the thymus gland is located on the dorsal side of the heart and aorta, and it plays a crucial role in the development of the immune system.

Solution approach

Correct Answer + Core Reason: A-dorsal, B-heart, C-immune. The thymus is dorsal to the heart and aorta, and it's key for immune system development.

Step-by-Step Solution:
Step 1: Recall the location of the thymus gland.
Step 2: The thymus is a lobular structure located on the dorsal side of the heart and aorta.
Step 3: The thymus plays a significant role in the development of the immune system, particularly in the maturation of T lymphocytes.
Step 4: Therefore, A is dorsal, B is heart, and C is immune.

Why other options are wrong:
- Option A: A-ventral, B-heart, C-immune is incorrect because the thymus is located on the dorsal side, not the ventral side.
- Option B: A-lateral, B-kidney, C-circulatory is incorrect because the thymus is located near the heart, not the kidneys, and it's involved in the immune system, not the circulatory system.
- Option D: A-dorsal, B-parathyroid, C-circulatory is incorrect because the thymus is located near the heart and aorta, not the parathyroid glands, and it's involved in the immune system, not the circulatory system.

Key Concepts:
- Thymus gland location
- Function of the thymus gland
- Immune system development

Memory Aids:
- Thymus = T cells (immune system)

Quick Tips:
- Remember the thymus is important for T cell maturation.

146 Easy

146 of 149

Remembering +4 | -1

Which of the following is the largest gland in an adult man?

View answer and explanation

Correct option: B

Liver

Option B (Liver) is correct because the liver is the largest internal organ in the human body by mass.

Solution approach

Correct Answer + Core Reason: Liver. The liver is the largest gland in the human body.

Step-by-Step Solution:

Step 1: The liver is the largest internal organ in the human body, weighing approximately 1.2-1.5 kg in an adult man.

Step 2: It performs various essential functions, including detoxification, protein synthesis, and the production of bile.

Step 3: The other options are smaller in size compared to the liver.

Why other options are wrong:
- Option A: The thymus is a gland located in the chest and is involved in immune function. It is much smaller than the liver.
- Option C: The thyroid is a gland located in the neck and produces thyroid hormones. It is smaller than the liver.
- Option D: The pancreas is a gland located in the abdomen and produces digestive enzymes and hormones. It is smaller than the liver.

Key Concepts:
- Liver
- Gland
- Organ size

Memory Aids:
- Think of the liver as the \"large\" and \"essential\" organ.

Quick Tips:
- Know the relative sizes of major organs in the human body.

147 Easy

147 of 149

Remembering +4 | -1

Which of the following hormone has an inactive form?

View answer and explanation

Correct option: B

Insulin

Option B (Insulin) is correct because insulin is synthesized as proinsulin, an inactive precursor, which is then cleaved to form active insulin.

Solution approach

Correct Answer + Core Reason: Insulin. Insulin is synthesized as an inactive precursor (proinsulin).

Step-by-Step Solution:

Step 1: Analyze Rennin: Rennin (chymosin) is secreted as an inactive proenzyme called prorennin (or chymosinogen) and is activated by stomach acid.

Step 2: Analyze Insulin: Insulin is synthesized as preproinsulin, then processed to proinsulin, which is then cleaved to form active insulin and C-peptide. Thus, insulin has an inactive form (proinsulin).

Step 3: Analyze Aldosterone: Aldosterone is directly synthesized and released without a significant inactive precursor form.

Step 4: Determine the correct answer: Since both Rennin and Insulin have inactive forms, but the question asks for one, and Insulin is the more direct answer related to hormone activity, Insulin is the best answer.

Why other options are wrong:
- Option A: Rennin does have an inactive form, but insulin is a more direct answer.
- Option C: Aldosterone does not have a significant inactive form.
- Option D: While both have inactive forms, the question asks for which hormone, and Insulin is the more direct answer.

Key Concepts:
- Prohormones
- Insulin synthesis
- Rennin activation
- Aldosterone synthesis

Memory Aids:
- Pro- = inactive precursor.

Quick Tips:
- Know the difference between hormones that are synthesized directly and those that are synthesized as prohormones.

148 Easy

148 of 149

Remembering +4 | -1

Select the hormone of adrenal cortex which is responsible for hyperglycaemia.

View answer and explanation

Correct option: C

Cortisol

Option C is correct because cortisol, a glucocorticoid, stimulates gluconeogenesis, leading to increased blood glucose levels (hyperglycemia).

Solution approach

Correct Answer + Core Reason: C. Cortisol. Cortisol is a glucocorticoid that promotes gluconeogenesis, leading to hyperglycemia.

Step-by-Step Solution:

Step 1: Recall the hormones produced by the adrenal cortex: mineralocorticoids (e.g., aldosterone), glucocorticoids (e.g., cortisol), and sex corticoids.

Step 2: Understand the function of each hormone: Aldosterone regulates electrolyte balance, cortisol regulates glucose metabolism, and sex corticoids influence secondary sexual characteristics.

Step 3: Cortisol increases blood glucose levels by stimulating gluconeogenesis (the production of glucose from non-carbohydrate sources).

Why other options are wrong:
- Option A: Aldosterone regulates sodium and potassium balance, not directly blood glucose levels.
- Option B: Epinephrine is produced by the adrenal medulla, not the cortex, and while it can increase blood glucose, it's not the primary hormone responsible for hyperglycemia from the adrenal cortex.
- Option D: Sex corticoids primarily affect sexual characteristics and have a minor role in glucose metabolism.

Key Concepts:
- Adrenal cortex hormones
- Glucocorticoids (cortisol)
- Mineralocorticoids (aldosterone)
- Gluconeogenesis
- Hyperglycemia

Memory Aids:
- Cortisol: Controls sugar (glucose)
- Aldosterone: Regulates salt (sodium)

Quick Tips:
- Differentiate between the roles of mineralocorticoids and glucocorticoids.

149 Easy

149 of 149

Remembering +4 | -1

Islets of Langerhans are found in

View answer and explanation

Correct option: D

Endocrine pancreas

Option D (Endocrine pancreas) is correct because the Islets of Langerhans are the hormone-producing clusters of cells within the pancreas.

Solution approach

Correct Answer + Core Reason: Endocrine pancreas. Islets of Langerhans are located within the endocrine pancreas.

Step-by-Step Solution:

Step 1: Recall the function of Islets of Langerhans: These are clusters of endocrine cells in the pancreas that produce hormones like insulin and glucagon.

Step 2: Consider the location: Since they are endocrine cells, they are found in the endocrine pancreas.

Why other options are wrong:
- Option A: Anterior pituitary is a separate endocrine gland in the brain.
- Option B: Kidney cortex is part of the kidney, responsible for filtration.
- Option C: Spleen is an organ involved in immune function and blood filtration.

Key Concepts:
- Islets of Langerhans
- Endocrine pancreas
- Hormone production

Memory Aids:
- Islets are "in" the endocrine pancreas.

Quick Tips:
- Know the major endocrine glands and their locations.

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