Tag: chemical coordination and integration

Questions Related to chemical coordination and integration

Choose the correct answer from the alternatives given.
Human sex hormones are classified as:

  1. amino acids

  2. lipids

  3. triacyiglycerols

  4. proteins


Correct Option: B
Explanation:

Human sex hormone is steroid hormones. The natural steroid hormones are generally synthesized from cholesterol in the gonads and adrenal glands. These forms of hormones are lipids. 

So the correct answer is lipids.

Choose the correct answer from the alternatives given.
Which of the following hormones is called an antidiuretic hormone?

  1. Glucagon

  2. Prolactin

  3. Vasopressin

  4. Cortisone


Correct Option: C
Explanation:

(A) Glucagon acts mainly on the liver cells and stimulates glycogenolysis resulting in increased blood sugar (hyperglycemia).

(B) Prolactin regulates the growth of the mammary glands and formation of milk in them. 
(C) Vasopressin or antidiuretic hormone (ADH) acts mainly at the kidney and stimulates resorption of water and electrolytes by the distal tubules and thereby reduce the loss of water through urine (diuresis). 
(D) Cortisone is the main glucocorticoid.
So the correct answer is vasopressin.

Which of the following statements is correct in relation to the endocrine system?

  1. Non-nutrient chemicals produced by the body in trace amount that act as intercellular messenger are known as hormones

  2. Releasing and inhibitory hormones are produced by the pituitary gland

  3. Adenohypophysis is under direct neural regulation of the hypothalamus

  4. Organs in the body like gastrointestinal tract, heart, kidney and liver to not produce any hormone


Correct Option: A
Explanation:

The endocrine system consists of organ, tissue and cells that produce a small amount of non-nutrient chemicals which sends signals to other cells or acts as an intercellular messenger. These chemicals are known as hormones which are transported to their target site through blood.

So the correct answer is 'Non-Nutrient chemicals produced by the body in trace amount that acts as intercellular messenger are known as hormones'.

Match the following


Sr No Column A Sr.no Column B
A. ADH 1. Pituitary
B. ACTH 2. Vasodilator
C. Insulin 3. Diabetes mellitus 
D. Adrenaline 4. Diabetes insipidus
   

  1. A=1,B=4,C=2,D=3

  2. A=4,B=2,C=1,D=3

  3. A=4,B=1,C=2,D=3

  4. A=4,B=1,C=3,D=2


Correct Option: D
Explanation:
 A.  ADH  ADH in the hypothalamus stores the hormone in the pituitary gland, a small gland located in the base of the brain. ADH is released into your bloodstream when your body starts to become dehydrated. ADH then concentrates the urine by triggering the kidney tubules to release water back into your bloodstream rather than excreting as much water into your urine. Disruption of this process causes Diabetes insipidusSo the correct option is 'Diabetes insipidus'
 B.  ACTH  Adrenocorticotropic hormone is a polypeptide tropic hormone produced by and secreted by the anterior pituitary gland. It is also used as a medication and diagnostic agent. ACTH is an important component of the hypothalamic-pituitary-adrenal axis and is often produced in response to biological stress.So the correction option is 'pituitary'
 C.  Insulin  Insulin is a hormone made by the pancreas that helps the body store and use glucose. Insulin is responsible for delivering that glucose (sugar) from the bloodstream into muscle, fat, liver, and most other cells of the body use it for as a fuel. Improper secretion of insulin causes diabetes mellitus.So the correct option is 'diabetes mellitus'
D Adrenaline Adrenaline, also known as epinephrine, is a hormone, neurotransmitter, and medication. Epinephrine is normally produced by both the adrenal glands and certain neurons. Key actions of adrenaline include increasing the heart rate, increasing blood pressure, expanding the air passages of the lungs, enlarging the pupil in the eye (see photo), redistributing blood to the muscles and altering the body's metabolism, so as to maximise blood glucose levels.So, the correct answer is 'Adrenaline'
   

Which of the following statements regarding hormones is incorrect?

  1. Hormones are non-nutrient chemicals which acts as intercellular messengers

  2. Hormones are molecules of low molecular weight and are produced in traces

  3. Hormones provide energy and also effect growth and metabolic activities of target cell

  4. Many hormones are produced in inactive form


Correct Option: C
Explanation:

Hormones do not provide energy or building materials but they effect growth, differentiation and metabolic activities of their target cell.

Proteins perform many physiological functions. For example, some proteins function as enzymes. One of the following represents an additional function that some proteins perform
  1. antibiotics

  2. pigment conferring colour to skin

  3. pigment making colours of flowers

  4. hormones


Correct Option: D
Explanation:

Most of the body functions are regulated by hormones like growth, vegetative and sexual development, thermal regulation, cellular oxidation, metabolism of carbohydrates, proteins, fats, etc. Hormones are needed in very small quantity to carry out these functions. Some hormones are proteinaceous eg: insulin (regulates sugar metabolism), growth hormone of pituitary, parathyroid hormone parathormone (regulates calcium and phosphate transport).

Choose the correct answer from the alternatives given.
Which of the following is not involved in calcium metabolism?

  1. Calmodulin

  2. Calcitonin

  3. Parathyroid hormone

  4. Atrial natriuretic factor


Correct Option: D
Explanation:

(A)Calmodulin is a multifunctional intermediate calcium binding messenger protein expressed in all eukaryotic cells. It is an intracellular target of the secondary messenger Ca2+, and the binding of Ca2+ is required for the activation of calmodulin. 

(B) Calcitonin is a hypocalcemic hormone. This is secreted by the C-cells in the thyroid gland. It acts on bone and the kidney to reduce the blood calcium level. It reduces the reabsorption of calcium from bones and inhibits reabsorption of calcium by the renal tubules.
(C) The parathyroid gland secretes a peptide hormone called parathyroid hormone (PTH). The secretion of PTH is regulated by the circulating levels of calcium ions. PTH increases the calcium levels in the blood. PTH also stimulates reabsorption of calcium by the renal tubules and increase calcium absorption from the digested food.
(D) Atrial Natriuretic Factor (ANF) is released when there is an increase in blood flow to the atria of the heart. ANF can cause vasodilation (dilation of blood vessels) and thereby decrease the blood pressure. ANF mechanism, therefore, acts as a check on the renin-angiotensin mechanism.
So the correct answer is the Atrial Natriuretic Factor. 

Choose the correct answer from the alternatives given.
Steroid hormones mediate their action by:

  1. activating adenylate cydase

  2. activating gene expression

  3. binding to the surface membrane of the cells

  4. inhibiting an enzyme


Correct Option: B
Explanation:

Steroid hormones and thyroid hormones do not bind to the cell surface receptors. Being lipid soluble, these are able to enter the cells and their nuclei and influence the gene action. The hormone binds to the receptors forming a hormone-receptor complex. It binds to the transcription factors that in turn to DNA and a particular gene is activated. Their transcription leads to the synthesis of a specific protein to influence the metabolism of the recipient cell. Thus, the peptide hormones activate existing enzymes in the cell while steroid hormones bring about the synthesis of new enzymes.

So the correct answer is activating gene expression.

Which of these is a correct statement? 

  1. Neurons regulate endocrine activity but not vice versa.

  2. Endocrine glands regulate neural activity and nervous system regulates endocrine glands.

  3. Neither hormones control neural activity nor neurons control endocrine activity.

  4. Endocrine glands regulate neural activity but not vice versa.


Correct Option: B
Explanation:

  • Nervous system is a coordinated network of nerve cells and fibres by which nerve impulses are transmitted throughout the body.
  • Endocrine system consists of glands that produce hormones.
In our body, nervous system and endocrine system jointly integrate all the activities as nervous system directs endocrine system to secrete hormones that act on the target organs.
So, the correct answer is 'Endocrine glands regulate neural activity and nervous system regulates endocrine glands.'.

Consider the following statements (a-d) and select the option which includes the correct ones only.
(a) The thyroid hormone plays an important role in the maintenance of the basal metabolic rate & erythropoiesis.
(b) Glucocorticoids inhibit inflammatory reactions by suppressing the immune system and promote erythropoiesis.
(c) Androgens promote development, maturation & function of the male sex organs as well as erythropoiesis.
(d) The gastrointestinal tract not only secretes gastric inhibitory peptide but also promotes the formation of RBCs.

  1. 4

  2. 3

  3. 2

  4. 1


Correct Option: A
Explanation:
In the given question, all the statements are correct as they all mention the correct function and effect of their respective hormones.
So, the correct answer is '4'.