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All questions of The Digestive System for Grade 9 Exam

The main function of prolactin hormone is to :-
  • a)
    Influence the activity of thyroid gland
  • b)
    Control development of graffian follicles
  • c)
    Initiate and maintain secretion of milk by mammary gland
  • d)
    Cause ejection of milk
Correct answer is option 'C'. Can you explain this answer?

Ananya Das answered
Prolactin, also called as luteotropic hormone (LTH) or luteotropin, is a protein hormone produced by the pituitary gland of mammals, that acts with other hormones to initiate secretion of milk by the mammary glands. 
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Which of the following is NOT an endocrine gland?
a)Salivary gland
b)Pituitary gland
c)Parathyroid gland
d)Pancreas gland
Correct answer is option 'A'. Can you explain this answer?

Rohit Jain answered
Endocrine glands are ductless glands of the endocrine system that secrete their products, hormones directly into the blood. The major glands of the endocrine system include the pineal gland, pituitary gland, pancreas, ovaries, testes, thyroid gland, parathyroid gland, hypothalamus and adrenal glands.

Hormone of hypothalamus are called :-
  • a)
    Growth hormones 
  • b)
    Regulatory hormones
  • c)
    Angiotensins
  • d)
    None of these
Correct answer is option 'B'. Can you explain this answer?

Rajat Kapoor answered
The hormones of the hypothalamus are called regulatory hormones. The hypothalamus is considered the master regulator of the endocrine system. 

 Which hormone among these is not secreted by an endocrine gland?
  • a)
    T4
  • b)
    MSH
  • c)
    ANF
  • d)
    ADH
Correct answer is option 'C'. Can you explain this answer?

Rajat Kapoor answered
Atrial natriuretic factor (ANF) is a 28 amino acid polypeptide hormone secreted mainly by the heart atria in response to atrial stretch. ANF acts on the kidney to increase sodium excretion and GFR, to antagonize renal vasoconstriction, and to inhibit renin secretion.

Gonadotrophic hormone is produced by :-
  • a)
    Interstitial cells of testis
  • b)
    Adrenal cortex
  • c)
    Adenohypophysis
  • d)
    Posterior part of thyroid
Correct answer is option 'C'. Can you explain this answer?

Kadambala Hemalatha answered
Option c is correct becose i will eliminate one by one option interstial cells (leading cells) produce androgens, adrenal cortex produce corticodis (glucocorticoids, minaralo corticodis), posterior part of thyroid gland is contains parathyroid glad it realese parathyroid hormone (hyper calcimic hormone),adenohypophysis (anterior pituitary, pars distalise) relese gondotrophic harmones (both FSH, LH).

Which of the following controls spermatogenesis :-
  • a)
    FSH
  • b)
    LTH
  • c)
    LH
  • d)
    Vasopressin
Correct answer is option 'A'. Can you explain this answer?

Nithya Sri answered
Frnd,
actually the correct answer might be LH
bcuz lh acts on leydig cells which enhance the production of androgens and controls spermatogenesis

Neurohypophysis secretes :-
  • a)
    Vasopressin
  • b)
    Oxytocin
  • c)
    Oxytocin & prolactin
  • d)
    Vasopressin & oxytocin
Correct answer is option 'D'. Can you explain this answer?

Sai Nikhil answered
Neurohypophysis secretes vasopressin&oxytocin vasopressin is for antidiuretic & oxytocin constrict smooth muscles to give pressure to milk to pass through mammary gland

Hormone secreted by pituitary gland is chemically
  • a)
    All protein
  • b)
    All steroid
  • c)
    Complex compounds of proteins and carbohydrates
  • d)
    Some steroid and some protein
Correct answer is option 'A'. Can you explain this answer?

Rajat Kapoor answered
The pituitary gland is a small gland that sits in the sella turcica (‘Turkish saddle’), a bony hollow in the base of the skull, underneath the brain and behind the bridge of the nose. The pituitary gland has two main parts, the anterior pituitary gland and the posterior pituitary gland. The gland is attached to a part of the brain (the hypothalamus) that controls its activity. The anterior pituitary gland is connected to the brain by short blood vessels. The posterior pituitary gland is actually part of the brain and it secretes hormones directly into the bloodstream under the command of the brain. 

"Sella turcica" is a :-
  • a)
    Depression in brain enclosing pituitary
  • b)
    Cavity of skull enclusing ears
  • c)
    Covering of testis
  • d)
    Kind of endocrine gland
Correct answer is option 'A'. Can you explain this answer?

Krishna Iyer answered
Sella trucia or 'Turkish saddle' is a depression in the floor of the mammalian skull in the sphenoid (Basi spenoid) bone in which the pituitary gland is lodged. It is also found in skull of chimpanzees, gorilla etc.

Gorilla like man with large head and hands and protruding Jaws is produced due to :-
  • a)
    Over-secretion of thyroxine
  • b)
    Over-secretion of growth hormone
  • c)
    Excess of vitamin C in diet
  • d)
    Excess secretion of TSH
Correct answer is option 'B'. Can you explain this answer?

Kadambala Hemalatha answered
Option B is correct becose over secretion of growth harmone (somatotripin) is causes acromagale due to this deasese gorilla like appearance occurs.due to low secretion of growth harmone causes gigantism also called as pituitary dwarf.

Diabetes insipidus disease is caused due to the deficiency of hormone produced by :-
  • a)
    Pituitary
  • b)
    Adrenal
  • c)
    Pancreas
  • d)
    Thyroid
Correct answer is option 'A'. Can you explain this answer?

Om Desai answered
Diabetes insipidus is a pathological endocrine condition characterized by excessive thirst and excessive production of very dilute urine. The disorder is caused by a lack of antidiuretic hormone (vasopressin) or a blocking of its action. This hormone, produced by the hypothalamus, regulates the kidney's conservation of water and production of urine through its ability to stimulate reabsorption of water by the kidneys. Hence, Option A.

Hypophysis cerebri is the other name of :-
  • a)
    Adenohypo physis
  • b)
    Islets of langerhans
  • c)
    Neurohypophysis
  • d)
    Pituitary gland
Correct answer is option 'D'. Can you explain this answer?

Supriya Senapati answered
Pituitary gland. Located at the base of the brain, the pituitary gland is protected by a bony structure called the sella turcica of the sphenoid bone.

The term hypophysis (from the Greek for “lying under”)—another name for the pituitary—refers to the gland's position on the underside of the brain.

Pituitary gland is under control of :-
  • a)
    Hypothalamus
  • b)
    Adrenal gland
  • c)
    Pineal gland
  • d)
    Thyroid gland
Correct answer is option 'A'. Can you explain this answer?

Nutan Jaiswal answered
Pituitary gland is also known as master gland which is under the control of of hypothalamus which is also known as master of master gland.

I.C.S.H. in male acts on :-
  • a)
    Cells of leydig
  • b)
    Sertoli cells
  • c)
    Spermatids
  • d)
    Spermatogonia
Correct answer is option 'A'. Can you explain this answer?

Mahi Desai answered
**I.C.S.H. in Male Acts on Cells of Leydig**

ICSH (interstitial cell-stimulating hormone), also known as LH (luteinizing hormone), is a hormone produced and released by the anterior pituitary gland. In males, ICSH/LH primarily acts on the cells of Leydig in the testes.

**1. Functions of ICSH/LH in Males:**
ICSH/LH plays a crucial role in the regulation of male reproductive functions. Its main functions include:

1. **Stimulation of Testosterone Production:** The primary function of ICSH/LH in males is to stimulate the Leydig cells to produce and release testosterone. Leydig cells are located in the interstitial spaces of the testes and are responsible for the synthesis and secretion of testosterone.

2. **Maintenance of Testosterone Levels:** ICSH/LH maintains the optimal levels of testosterone in the blood. Testosterone is an essential hormone involved in various physiological processes, including the development and maintenance of male reproductive organs, secondary sexual characteristics, and spermatogenesis.

3. **Stimulation of Sperm Production:** Testosterone, under the influence of ICSH/LH, promotes the process of spermatogenesis, which is the production of sperm. It acts on the Sertoli cells, which are located within the seminiferous tubules of the testes and support the development and maturation of sperm cells.

**2. Target Cells of ICSH/LH in Males:**
ICSH/LH primarily acts on the cells of Leydig in the testes. These target cells include:

**a) Cells of Leydig:** ICSH/LH binds to specific receptors on the surface of Leydig cells, triggering a series of biochemical reactions within the cells. This leads to the production and release of testosterone into the bloodstream. Testosterone then acts on various target tissues and cells throughout the body, exerting its effects.

**b) Sertoli Cells:** Although ICSH/LH does not directly act on Sertoli cells, it indirectly influences their function. Testosterone, which is stimulated by ICSH/LH, acts on Sertoli cells to support the development and maturation of sperm cells during spermatogenesis.

**c) Spermatids:** Spermatids are the immature sperm cells formed during the process of spermatogenesis. ICSH/LH indirectly influences the development of spermatids by stimulating testosterone production, which acts on Sertoli cells to support their maturation into fully functional sperm cells.

**d) Spermatogonia:** Spermatogonia are the germ cells in the testes that undergo mitosis to produce more spermatogonia or differentiate into spermatocytes, which further develop into spermatids. ICSH/LH indirectly influences spermatogonia by promoting spermatogenesis and the development of mature sperm cells.

In summary, ICSH/LH acts primarily on the cells of Leydig in the testes, stimulating the production and release of testosterone. Testosterone, in turn, influences Sertoli cells, spermatids, and spermatogonia, supporting the process of spermatogenesis and the development of mature sperm cells.

The hormones FSH and LH are together called :-
  • a)
    Emergency hormone
  • b)
    Neuro hormone
  • c)
    Gonadotrophic hormone
  • d)
    Antistress hormone
Correct answer is option 'C'. Can you explain this answer?

Geetika Shah answered
The hormones FSH and LH are together called as gonadotropin hormones. They are called the gonadotropins as they stimulate gonadal activity. The anterior pituitary (pars distalis) releases following gonadotrophic hormones:
Follicle stimulating hormone (FSH): In males, FSH regulates spermatogenesis (formation of sperms) and in females, FSH stimulates growth and development of ovarian follicles and secretion of estrogen hormone.
Luteinizing hormone (LH): In males, LH is also called ICSH (interstitial cell-stimulating hormone) which stimulates testes to synthesize and secrete androgens (testosterone). It activates Leydig cells of the testes to secrete testosterone. In females, LH stimulates the ovulation of the fully matured Graafian follicles and also maintains the corpus luteum, formed from the remnants of Graafian follicles after ovulation. The corpus luteum secretes progesterone and some estrogen under the action of LH.
So, the correct answer is 'Gonadotropic hormone'.

FSH & LH is a :-
  • a)
    Catecholamine
  • b)
    Glycoprotein
  • c)
    Polypeptide
  • d)
    None
Correct answer is option 'B'. Can you explain this answer?

Ayush Joshi answered
The gonadotropins, a family of closely related glycoprotein hormones, include follicle stimulating-hormone (FSH) and luteinizing hormone (LH) which are produced by the same pituitary cells, the gonadotrophs and chorionic gonadotropin (CG) which is of placental origin.

Which of the following is called emergency gland of the body?
  • a)
    Testis
  • b)
    Adrenal Medulla
  • c)
    Thymus
  • d)
    Pituitary
Correct answer is option 'B'. Can you explain this answer?

Vivek Patel answered
Adrenal gland is called the emergency gland of the body. Adrenaline is secreted by adrenal medulla on stimulation by sympathetic nervous system for meeting an emergency of stress condition, like injury, pain fear, Accident, grief, fall in blood pressure etc. Hence adrenal gland is called emergency hormone.

Gigantism and acromegaly are due to :-
  • a)
    Hyperpituitrism
  • b)
    Hypopituitrism
  • c)
    Hypothyroidism
  • d)
    Hyperthyroidism
Correct answer is option 'A'. Can you explain this answer?

Gaurav Kumar answered
Gigantism and acromegaly occur when the pituitary gland makes too much growth hormone (hyperpituitarism) due to a tumor on the gland. The difference between acromegaly and gigantism is that acromegaly occurs in adults, typically between the ages of 30 and 50. Hence, option A is correct.

Which is called "Master gland" of the body :-
  • a)
    Thyroid
  • b)
    Pituitary
  • c)
    Thymus
  • d)
    Adrenal
Correct answer is option 'B'. Can you explain this answer?

User5881746 answered
Pituitary gland controls the secretion of the most of the hormones in the humane body so it is called master gland

Can you explain the answer of this question below:

Vasopressin is responsible for :-

  • A:

    Controlling Oogenesis

  • B:

    Regulating blood pressure and act on the nephron tubules.

  • C:

    Regulating formation of pigment.

  • D:

    Controlling spermatogenesis.

The answer is b.

Saumya Ahuja answered
Ans.

Vasopressin, also called antidiuretic hormone, hormone that plays a key role in maintaining osmolality (the concentration of dissolved particles, such as salts and glucose, in the serum) and therefore in maintaining the volume of water in the extracellular fluid (the fluid space that surrounds cells).

Urine concentration is controlled by :-
  • a)
    Oxytocin
  • b)
    ADH
  • c)
    MSH
  • d)
    ACTH
Correct answer is option 'B'. Can you explain this answer?

Vishal Kumar answered
Regulation of Urine Concentration and Volume Antidiuretic hormone (ADH) is produced by the pituitary gland to control the amount of water that is reabsorbed through the collecting of urine.

The same hormone can be known by various names given in which set :-
  • a)
    Secretin, enterokinin, gastrin
  • b)
    Gametokinetic factor, testosterone, LTH
  • c)
    ADH, pitressin, and vasopressin
  • d)
    Oxytocin, tri-iodo-thyronine, thyroxine
Correct answer is option 'C'. Can you explain this answer?

Gaurav Kumar answered
Antidiuretic hormone (ADH) is secreted by the posterior pituitary gland and targets nephrons to increase water reabsorption and thereby decreasing water content in urine. The man-made form of ADH hormones is named as vasopressin which is administered to the patient with diabetes insipidus. Thu, the correct answer is C.

The source of somatostatin is same as that of
  • a)
    Thyroxine and calcitonin
  • b)
    Insulin and glucagon
  • c)
    Somatotropin and prolactin
  • d)
    Vasopressin and adrenline
Correct answer is option 'B'. Can you explain this answer?

Dev Patel answered
Insulin, glucagon and somatostatin, are secreted by islets of Langerhans of pancreas, Somatostatin suppresses the release of other hormones from pancreas.

Which gland secretes hormones involved in the 'fight or flight' response?
  • a)
    Thyroid gland
  • b)
    Adrenal medulla
  • c)
    Pancreas
  • d)
    Parathyroid gland
Correct answer is option 'B'. Can you explain this answer?

Avantika Chavan answered
Introduction
The 'fight or flight' response is a physiological reaction that occurs in response to a perceived threat, involving several hormones that prepare the body for rapid action. The gland primarily responsible for secreting these hormones is the adrenal medulla.
Adrenal Medulla's Role
- The adrenal medulla is the inner part of the adrenal glands, located on top of each kidney.
- It is responsible for releasing catecholamines, primarily adrenaline (epinephrine) and norepinephrine.
Hormones Involved
- Adrenaline (Epinephrine): Increases heart rate, dilates air passages, and boosts energy supplies.
- Norepinephrine: Works alongside adrenaline to increase blood flow to muscles and elevate blood pressure.
Effects on the Body
- These hormones trigger several immediate physiological changes, such as:
- Increased heart rate and blood pressure.
- Dilated pupils for improved vision.
- Enhanced energy availability by mobilizing glucose and fatty acids.
- Dilation of bronchial passages for better oxygen intake.
Comparison with Other Glands
- Thyroid Gland: Produces hormones that regulate metabolism but is not directly involved in the 'fight or flight' response.
- Pancreas: Secretes insulin and glucagon, which regulate blood sugar levels but do not initiate the stress response.
- Parathyroid Gland: Regulates calcium levels in the blood and has no role in acute stress responses.
Conclusion
In summary, the adrenal medulla is crucial for the 'fight or flight' response, as it secretes hormones like adrenaline and norepinephrine that prepare the body for immediate action in stressful situations.

MSH is secreted by
  • a)
    Anterior lobe of pituitary
  • b)
    Middle lobe of pituitary
  • c)
    Posterior lobe of pituitary
  • d)
    Endostyle
Correct answer is option 'B'. Can you explain this answer?

Anjali Sharma answered
Middle lobe of pituitary secretes MSH (melanocyte stimulating hormone) that controls the synthesis of melanin granules in the chromatophores.

TSH (thyroid stimulating hormone) is produced by
  • a)
    adrenal cortex
  • b)
    middle pituitary lobe
  • c)
    anterior pituitary lobe
  • d)
    posterior pituitary lobe
Correct answer is option 'C'. Can you explain this answer?

Naveen Desai answered
TSH (thyroid stimulating hormone) is produced by the anterior pituitary lobe. The anterior pituitary is a small gland located at the base of the brain that is responsible for producing and releasing various hormones that regulate different functions in the body.

- TSH is one of the many hormones produced by the anterior pituitary and plays a crucial role in the regulation of the thyroid gland. The thyroid gland is located in the neck and is responsible for producing thyroid hormones that are essential for normal growth, development, and metabolism.

- The production of TSH is regulated by a negative feedback loop involving the hypothalamus, anterior pituitary, and thyroid gland. When the levels of thyroid hormones in the blood are low, the hypothalamus releases thyrotropin-releasing hormone (TRH), which stimulates the anterior pituitary to release TSH.

- TSH then acts on the thyroid gland, stimulating the production and release of thyroid hormones, primarily thyroxine (T4) and triiodothyronine (T3). These hormones play a vital role in regulating the body's metabolism, growth, and development.

- Once the levels of thyroid hormones in the blood reach a certain threshold, they inhibit the release of TRH and TSH through negative feedback. This helps to maintain a stable balance of thyroid hormones in the body.

- TSH also plays a role in the growth and development of the thyroid gland itself. In conditions such as hypothyroidism or goiter, where the thyroid gland is underactive or enlarged, respectively, the levels of TSH may be elevated as the body tries to compensate for the decreased production of thyroid hormones.

- In summary, TSH is produced by the anterior pituitary and plays a crucial role in the regulation of thyroid function. It stimulates the production and release of thyroid hormones, which are essential for normal growth, development, and metabolism.

Which of the following statements is true regarding hormone receptors?
  • a)
    Each receptor is specific to one hormone only.
  • b)
     Hormone receptors can bind to multiple hormones simultaneously.
  • c)
    Hormone receptors are found only in the liver.
  • d)
    Hormone receptors are only located on the cell membrane.
Correct answer is option 'A'. Can you explain this answer?

Upasana Sharma answered
Understanding Hormone Receptors
Hormone receptors are crucial components in the endocrine system, facilitating communication between hormones and target cells. The correct statement regarding hormone receptors is that each receptor is specific to one hormone only.
Specificity of Hormone Receptors
- Unique Binding: Each hormone receptor has a unique shape and structure that allows it to bind specifically to its corresponding hormone. This specificity ensures that the correct signaling pathways are activated in the target cells.
- Examples: For instance, insulin receptors only bind insulin, while thyroid hormone receptors only bind thyroid hormones. This precise interaction is essential for maintaining homeostasis in the body.
Misconceptions About Hormone Receptors
- Multiple Hormones: Contrary to option 'B', hormone receptors do not bind to multiple hormones simultaneously. Each receptor is tailored to respond to a specific hormone, preventing cross-reactivity and ensuring precise physiological responses.
- Location: Option 'C' is also misleading. Hormone receptors are not limited to the liver; they are present in various tissues throughout the body, including muscles, fat, and the brain, adapting to the local hormone environment.
- Placement: Regarding option 'D', hormone receptors can be found both on the cell membrane (for water-soluble hormones) and inside the cell (for lipid-soluble hormones), indicating a versatile distribution.
Conclusion
In summary, the specificity of hormone receptors to individual hormones is crucial for the precise regulation of physiological processes. Understanding this concept is fundamental for studies in endocrinology, particularly for NEET aspirants.

What is the primary function of prolactin secreted by the anterior pituitary gland?
  • a)
    Stimulate testosterone production
  • b)
    Increase water reabsorption in kidneys
  • c)
    Regulate growth and development of mammary glands
  • d)
    Stimulate melanin production
Correct answer is option 'C'. Can you explain this answer?

Avantika Chavan answered
Introduction to Prolactin
Prolactin is a hormone produced by the anterior pituitary gland, primarily known for its role in regulating various reproductive and metabolic functions.
Primary Function
- The main function of prolactin is to regulate growth and development of mammary glands.
- It plays a critical role during pregnancy and lactation, promoting the development of mammary tissues and the synthesis of milk.
Mechanism of Action
- Prolactin levels increase during pregnancy, preparing the breasts for milk production.
- After childbirth, the suckling of an infant stimulates further secretion of prolactin, ensuring milk is produced as needed.
Other Functions
- While its primary role is associated with mammary glands, prolactin also has effects on:
- Immune system regulation
- Metabolic processes
- Reproductive health (inhibiting ovulation temporarily during breastfeeding)
Why Other Options Are Incorrect
- a) Stimulate testosterone production: This function is primarily regulated by luteinizing hormone (LH).
- b) Increase water reabsorption in kidneys: This function is associated with antidiuretic hormone (ADH or vasopressin).
- d) Stimulate melanin production: Melanin production is mainly influenced by melanocyte-stimulating hormone (MSH).
Conclusion
In summary, prolactin's primary function is the regulation of mammary gland development and milk production, making option 'C' the correct answer. Understanding the specific roles of hormones like prolactin is crucial for grasping their impact on human physiology.

The blood calcium level is lowered by the deficiency of
  • a)
    Thyroxine
  • b)
    Calcitonin
  • c)
    Parathormone
  • d)
    Both (a) and (b)
Correct answer is option 'C'. Can you explain this answer?

Dev Patel answered
Parathormone secreted by parathyroid gland regulates the level of calcium in the blood. It stimulates the release of calcium from the bones into the blood, increases calcium absorption from the intestine into the blood and it also increases calcium reabsorption from the nephrons into the blood. Therefore, its deficiency leads to low blood calcium level.

The given table enlists various hormones and their chemical nature. Select the option which completes the table.

  • a)
    A
  • b)
    B
  • c)
    C
  • d)
    D
Correct answer is option 'D'. Can you explain this answer?

Gaurav Kumar answered
(i) Peptides: These hormones are further of two types: Short peptide and long peptide.
Short peptide: The hormones oxytocin and vasopressin from the posterior lobe of the pituitary gland.
Long peptide: The hormones insulin and glucagon from the pancreas.
(ii) Steroid: The hormones from adrenal cortex, testes, ovaries and placenta are steroids. So, testosterone is a steroid.
(iii) Amino acid derivative: The hormones epinephrine and norepinephrine from the adrenal medulla and thyroxine from the thyroid gland are derived from the amino acid tyrosine.
So, the correct answer is '(i)- Oxytocin, (ii)- Steroid, (iii)- Iodothyronine, (iv)- Epinephrine'.

Which hormone causes dilation of blood vessels, increased oxygen consumption and glucogenesis?
  • a)
    Glucagon
  • b)
    ACTH
  • c)
    Insulin
  • d)
    Adrenalin
Correct answer is option 'D'. Can you explain this answer?

Ajay Yadav answered
Adrenaline (Epinephrine) hormone is secreted by adrenal medulla under the conditions of emergency. Therefore, it is also known as emergency hormone. During emergency, it is released and causes dilation of blood vessels, so that the blood flow is increased. It also increases heart beat so that more oxygen is consumed and it also increases blood glucose level.

Which of the following sentences about steroid hormones is false?
  • a)
    They act by affecting gene expression.
  • b)
    They can pass through nuclear membranes.
  • c)
    The steroid hormone-receptor complex binds to hormone response elements in DNA.
  • d)
    Steroid hormones are proteinaceous in nature. 
Correct answer is option 'D'. Can you explain this answer?

Prasenjit Chavan answered

False Statement about Steroid Hormones:




Steroid Hormones are Proteinaceous in Nature:
- This statement is false because steroid hormones are not proteinaceous in nature. They are actually derived from cholesterol and are lipid-based molecules.
- Steroid hormones are synthesized in the endocrine glands such as the adrenal glands, gonads, and placenta.
- These hormones are characterized by their ability to pass through cell membranes easily due to their lipid nature.

Correct Statements about Steroid Hormones:
- They act by affecting gene expression: Steroid hormones bind to specific receptors inside the cell and then move into the nucleus where they can affect gene expression.
- They can pass through nuclear membranes: Steroid hormones are lipid-soluble molecules that can easily pass through the nuclear membrane to bind to their receptors inside the cell.
- The steroid hormone-receptor complex binds to hormone response elements in DNA: Once the steroid hormone binds to its receptor, the complex can bind to specific hormone response elements in the DNA, leading to changes in gene expression.

Estrogens are synthesized and secreted by which of the following structures in females?
  • a)
    Corpus luteum
  • b)
    Ovarian follicles
  • c)
    Adrenal cortex
  • d)
    Pineal gland
Correct answer is option 'B'. Can you explain this answer?

Avantika Chavan answered
Overview of Estrogen Synthesis
Estrogens are a group of hormones critical for female reproductive health, primarily involved in the development of secondary sexual characteristics and the regulation of the menstrual cycle.
Key Structures Involved in Estrogen Production
- Ovarian Follicles
- The primary site for estrogen synthesis in females is the ovarian follicles.
- Follicles contain granulosa cells that convert androgens (produced by theca cells) into estrogens like estradiol.
- This process is stimulated by follicle-stimulating hormone (FSH) from the pituitary gland.
- Corpus Luteum
- After ovulation, the corpus luteum forms from the remnants of the follicle.
- While it produces some estrogen, its main function is to secrete progesterone.
- Adrenal Cortex
- The adrenal cortex can produce small amounts of estrogens, but its primary role is in the synthesis of adrenal hormones such as cortisol and aldosterone.
- Pineal Gland
- The pineal gland primarily produces melatonin and does not play a significant role in estrogen synthesis.
Conclusion
The correct answer is option 'B', as the ovarian follicles are the primary structures responsible for synthesizing and secreting estrogens in females. Understanding this hormonal process is crucial for comprehending female reproductive physiology and the hormonal regulation of the menstrual cycle.

Which hormone secreted by the pancreas lowers blood glucose levels?
  • a)
    Glucagon
  • b)
    Insulin
  • c)
    Somatostatin
  • d)
    Cortisol
Correct answer is option 'B'. Can you explain this answer?

Avantika Chavan answered
Understanding Insulin and Blood Glucose Levels
Insulin is a crucial hormone produced by the pancreas that plays a vital role in regulating blood glucose levels. Here's how it works:
Function of Insulin
- Lowering Blood Glucose: After you eat, carbohydrates are broken down into glucose, which enters the bloodstream. Insulin is released in response to elevated blood glucose levels.
- Facilitating Cellular Uptake: Insulin stimulates cells, particularly muscle and fat cells, to absorb glucose from the bloodstream. This process lowers blood sugar levels.
Mechanism of Action
- Glycogenesis: Insulin promotes glycogenesis, the conversion of glucose into glycogen, which is stored in the liver and muscles for later use.
- Inhibition of Gluconeogenesis: Insulin inhibits gluconeogenesis, the process by which the liver produces glucose from non-carbohydrate sources, further contributing to the reduction of blood glucose levels.
Consequences of Insulin Deficiency
- Hyperglycemia: A lack of insulin or its ineffective action leads to elevated blood glucose levels, which can result in diabetes mellitus.
- Long-Term Complications: Chronic high blood sugar can lead to serious health issues, including cardiovascular disease, neuropathy, and kidney damage.
Conclusion
Insulin is essential for maintaining blood glucose homeostasis. Its primary function is to lower blood sugar levels by facilitating glucose uptake and storage, making it a critical hormone for metabolic health. This is why the correct answer to the question regarding which hormone lowers blood glucose levels is option 'B', Insulin.

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