CBSE Questions for Class 11 Medical Biology Chemical Coordination And Integration Quiz 3 - MCQExams.com

$$\textbf{Correct option:B}$$ 

$$\textbf{Solution:}$$

$$\bullet$$ The  glands which can function as both exocrine and endocrine are known as heterocrine glands and pancreas is a heterocrine .

$$\textbf{Correct option:C}$$ 

$$\textbf{Solution:}$$

$$\textbf{Option (A)}$$

$$\bullet$$ Vasopressin secreted from the neurosecretory cells of hypothalamus plays a crucial role in the reabsorption of water from glomerular filtrate ,excreting hypertonic urine and maintaining a balanced fluid content in the body.

$$\textbf{Option (B)}$$

$$\bullet$$ Corticosterone is another glucocorticoid released from the adrenal cortex that is involved in regulation of energy, immune reactions, and stress responses.

$$\textbf{Option (C)}$$

$$\bullet$$ Aldosterone is a mineralocorticoid secreted by the adrenal medulla which increases the permeability of nephron to sodium ions and increases reabsorption of sodium ions  from kidneys which further results in withdrawing water from glomerular filtrate . 

$$\bullet$$  Therefore ,there is an overall rise in sodium and water in blood and plasma. 

$$\textbf{Option (D)}$$

$$\bullet$$ Progesterone is secreted from a temporary gland corpus luteum,it maintains the endometrium lining of uterine walls during pregnancy,develops mammary glands,helps in the formation of placenta,embryonal development and implantation.

$$\textbf{Hence, the correct option is (C)}$$

• Adrenaline and noradrenaline hormones are secreted by the adrenal medulla part of the adrenal gland.
• Adrenaline and noradrenaline are rapidly secreted in response to the stress of any kind and during emergency situations and are called emergency hormones or hormones of Fight or Flight. Both the hormones increase the heart rate supply of blood, the strength of heart contraction and the rate of respiration.
• Hence Adrenaline increases heart rate and supply of blood to various organs is a correct statement.
• So, the correct answer is 'Adrenaline increases heart rate and supply of blood to various organs'.

• The hormone from the thyroid gland is thyroxine. 
• Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. 
• It plays vital roles in digestion, heart and muscle function, brain development, and maintenance of bones. 
• Thyroxine (contains 4 iodine molecules) is the inactive form and most of it is converted to an active form, called triiodothyronine by removing one iodine molecule.

$$\textbf{Correct option:D}$$ 

$$\textbf{Solution:}$$

$$\textbf{Option (A)}$$

$$\bullet$$ Gonadotropic hormones are secreted from the anterior lobe of pituitary which are follicle stimulating hormone which stimulates the secretion of estrogens from developing graafian follicles and luteinizing hormones stimulated the secretion of progesterone from corpus luteum and androgens from leydig's cells.

$$\textbf{Option (B)}$$

$$\bullet$$ Hypothalamus secretes gonadotropin releasing hormone that stimulates the release of sex hormones from adenohypophysis.

$$\textbf{Option (C)}$$

$$\bullet$$ Thyroid gland secretes three major hormone thyroxine,triiodothyronine and thyrocalcitonin. Thyroxine and triiodothyronine is required for prenatal mental development,temperature homeostasis and increases metabolism in body. Thyrocalcitonin helps with the calcium metabolism in the body.

$$\textbf{Option (D)}$$

$$\bullet$$ Both A and B.

$$\textbf{Hence, the correct option is (D)}$$

A) Correct option (B)
B) Explanation of the correct statement

Testosterone is a male hormone that is secreted from the testis of males and its function is to increase the masculine nature in the body after puberty.
It is not secreted by the pancreas. 

C) Explanation of the correct statement

Option (A)
Adrenaline is secreted from the adrenal gland which plays an important role during stress conditions increases blood flow from the heart and other visceral functions.

 Option (C)
Estrogen is a female hormone secreted from the ovary and is responsible for female sexual characteristics.

 Option (D)
Thyroxine is secreted from the thyroid gland which regulates the BMR of the body.

Insulin is a hormone produced by beta cells of the pancreas which plays a role in the absorption of sugar i. e glucose from the blood. When there is an insufficient insulin produced or when insulin is not produced at all, glucose levels in the blood rise and results in diabetes mellitus. As diabetes mellitus is a metabolic disorder characterized by increased glucose levels in the blood due to lack of insulin or low insulin secretion by the pancreas, the hormone insulin has to be injected in order to bring down the blood glucose to normal levels. So, the correct answer is option A.

• Pancreatic enzymes help break down fats, proteins, and carbohydrates. The pancreatic juice secreted into the duodenum contains pancreatic enzymes (lipase, protease, amylase) to help with digestion and bicarbonate to neutralize stomach acid as it enters the small intestine.

Correct answer: (A)

Renin is an enzyme released by kidneys when blood pressure is low. It converts angiotensinogen into angiotensin I. angiotensin I is then converted into angiotensin II by the enzyme ACE (angiotensin converting enzyme). Angiotensin II causes blood vessels to constrict and blood pressure to increase.

Explanation for correct matches:

Option (B): Ptyalin is a form of amylase produced by salivary gland that breaks down starch into simpler sugars like maltose and dextrin.

Option (C): Gastric chief cells of stomach secrete pepsinogen which becomes active as pepsin at low pH. Pepsin digests proteins into peptides.

Option (D): Pancreas produces trypsinogen which is inactive and releases it into small intestine where it is converted into trypsin. In the small intestine, trypsin catalyses the hydrolysis of peptide bonds and break down the proteins into smaller peptides.

• Pancreatic juice is a liquid secreted by the pancreas, which contains a variety of enzymes, including trypsinogen, chymotrypsinogen, elastase, carboxypeptidase, pancreatic lipase, nucleases and amylase. 
• Pancreatic juice is alkaline in nature due to the high concentration of bicarbonate ions. Hence, Pancreatic juice is alkaline in nature and contains a variety of enzymes.