Human Physiology MCQs focuses on “Chemical Coordination and Integration – Mechanism of Action of Insulin”.
1. Diabetes insipidus is due to insufficient release of _________
A. Insulin
B. ADH
C. Thyroxine
D. Glucagon
Answer: B
Clarification: Diabetes insipidus is a disorder of salt and water metabolism marked by intense thirst and heavy urination. Diabetes insipidus is due to insufficient release of ADH.
2. Which of the following gastrointestinal hormone stimulates insulin secretion?
A. GIP
B. CCK
C. Gastrin
D. Secretin
Answer: A
Clarification: GIP is gastroinhibitory peptide. It is also known as glucose dependent insulinotroic peptide. It is a weak inhibitor of gastric acid secretion; its main role is to stimulate insulin secretion.
3. Which of the following element is needed for insulin to exert its maximal effect in glucose uptake?
A. Vanadium
B. Molybdenum
C. Selenium
D. Chromium
Answer: D
Clarification: Chromium is an essential mineral that appears to have a beneficial role in the regulation of insulin action and its effects on carbohydrate, protein and lipid metabolism. Chromium is an important factor for enhancing insulin activity.
4. Insulin promotes _______
A. Glucosuria
B. Glycogenesis
C. Glycogenolysis
D. Gluconeogenesis
Answer: b
Clarification: Glycogenesis is a process of glycogen synthesis from sugar. Insulin promotes Glycogenesis.
5. Humulin is being commercially produced from a transgenic species of _______
A. Rhizobium
B. Saccharomyces
C. Escherichia
D. Mycobacterim
Answer: C
Clarification: Humulin is being commercially produced from a transgenic species of Escherichia. Humulin is a man-made form of hormone that is produced from the body. It was first done by Eli Lily company.
6. Insulin receptors are ___________
A. Extrinsic protein
B. Intrinsic protein
C. G protein
D. Trimeric protein
Answer: a
Clarification: Insulin receptors are extrinsic protein. Insulin binds to r4ecetors on the cell surface. This activates the cell’s glucose transporter molecules to form a doorway in the cell membrane so that glucose can enter the cell.
7. What do endocrine cells of the pancreas secrete?
A. Omega growth hormone
B. Beta somatostatin
C. Delta insulin
D. Alpha glucagon
Answer: d
Clarification: Alpha glucagon is secreted by endocrine cells of the pancreas. They make up to 20% of human islet cells synthesizing and secreting glucagon.
8. Where does synthesis of insulin begin?
A. rRER
B. sRER
C. Nucleolus
D. Mitochondria
View Answer
Answer: C
Clarification: Nucleolus is a part of eukaryote cell where ribosomes are made. It is the largest structure in the nucleus. Synthesis of insulin begins in Nucleolus.
9. How many intermolecular and interamolecular disulfide bond is present in insulin?
A. 1 Intermolecular, 2 intramolecular
B. 2 Intermolecular, 2 intramolecular
C. 2 Intermolecular, 1 intramolecular
D. 1 Intermolecular, 3 intramolecular
Answer: C
Clarification: There are 2 Intermolecular and 1 intramolecular disulfide bond is present in insulin.
10. Which of the following order is correct?
A. Insulin > Proinsulin > Preproinsulin
B. Preproinsulin > Insulin > Proinsulin
C. Proinsulin > Preproinsulin > Insulin
D. Preproinsulin > Proinsulin > Insulin
Answer: D
Clarification: Insulin is made up of two peptide chains referred to as A chain and B chain. A and B chains are linked together by disulfide bonds and an additional disulfide bond is formed within A chain.
11. What is the beta subunit of the insulin receptor?
A. Protein kinase
B. Tyrosine kinase
C. Tryptophan kinase
D. Taurine kinase
Answer: B
Clarification: Tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to a protein in the cell. It functions as an on or off switch in many cellular functions.
12. What do delta cells secrete?
A. Cortisol
B. Glucose
C. Pancreatic enzyme
D. Somatostatin
Answer: D
Clarification: Somatostatin is also known as growth hormone. It is a peptide hormone. Somatostatin is secreted by delta cells.
13. What is the function of GLUT 4?
A. Glucose transport
B. Glycogen transport
C. Insulin transport
D. Glucagon transport
Answer: A
Clarification: GLUT 4 is the insulin regulated glucose transporter found primarily in adipose tissues and striated muscle.
14. Hyperglycemia is a condition of high blood glucose.
A. True
B. False
Answer: A
Clarification: Hyperglycemia is an abnormally high blood glucose level. It is a sign of diabetes. The main symptoms are increased thirst and frequent need to urinate.