Consider statements about human immunity: 1. IgG is the most abundant antibody in blood. 2. IgE is involved in allergic reactions. 3. IgA is found in mucosal secretions. Which are correct? MCQ with Answer and Explanation

Question

Consider statements about human immunity: 1. IgG is the most abundant antibody in blood. 2. IgE is involved in allergic reactions. 3. IgA is found in mucosal secretions. Which are correct?

A. 1, 2 and 3

B. 2 and 3 only

C. 1 and 3 only

D. 1 and 2 only

Answer: Option A

Solution (By JKSSB Mock Tests)

Immunoglobulin G (IgG) is the most abundant antibody in blood plasma, providing long-term immunity and crossing the placenta. Immunoglobulin E (IgE) is present in small amounts and binds to mast cells, triggering the release of histamine during allergic reactions. Immunoglobulin A (IgA) is predominantly found in mucosal secretions like saliva, tears, and breast milk, providing localized mucosal immunity. All statements are correct.

This question belongs to: Science Biology

Request complete Subject PDF

Discuss this Question (0)

No comments yet. Be the first to start the discussion!

Practice More Biology Questions

Question #1

Share Report

Which digestive enzyme breaks down lactose into glucose and galactose?

A. Lactase

B. Maltase

C. Sucrase

D. Amylase

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option A

Explanation:
Lactase is a brush border enzyme of the small intestine that hydrolyzes the disaccharide lactose (milk sugar) into its constituent monosaccharides, glucose and galactose. Maltase acts on maltose, sucrase on sucrose, and amylase on starch. Lactose intolerance results from lactase deficiency, causing gastrointestinal symptoms after dairy consumption.

This question belongs to: Science Biology

Question #2

Share Report

Marasmus is a disease of severe malnutrition characterized by:

A. Edema and fatty liver

B. Bone deformities

C. Bleeding gums

D. Overall wasting of body tissues and severe calorie-protein deficiency

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option D

Explanation:
Marasmus is a form of severe malnutrition caused by a deficiency of both calories and protein. It results in extreme wasting of muscle and subcutaneous fat, making the child look emaciated or 'wasted'. Unlike kwashiorkor, marasmus typically does not present with edema. The child is extremely weak, has a 'old man' face, and is highly susceptible to infections.

This question belongs to: Science Biology

Question #3

Share Report

The scientist who proposed the 'indirect fit' model of enzyme action was:

A. Daniel Koshland

B. Maud Menten

C. Leonor Michaelis

D. Emil Fischer

View Answer & Solution Discuss

Get Complete Subject PDF for Science

Correct Answer: Option A

Explanation:
Daniel Koshland proposed the induced fit model (1958), where enzyme active site changes shape upon substrate binding. Fischer had proposed lock-and-key.

This question belongs to: Science Biology

Explore All Biology MCQs