Biology - Study Mode

[#961] Antigen is a substance which
Correct Answer

(C) Triggers the immune system

Explanation

Solution: An antigen is any substance that causes your immune system to produce antibodies against it. This means your immune system does not recognize the substance, and is trying to fight it off. An antigen may be a substance from the environment, such as chemicals, bacteria, viruses, or pollen.

[#962] AIDS is caused by the organisms which are
Correct Answer

(C) Viruses (HIV)

Explanation

Solution: Acquired immunodeficiency syndrome (AIDS) is a chronic, potentially life-threatening condition caused by the human immunodeficiency virus (HIV).

[#963] Blood group which have no antibodies
Correct Answer

(C) AB

Explanation

Solution: Blood group AB – has both A and B antigens, but no antibodies.

[#964] The sound lub-dub lub-dub is produced by
Correct Answer

(C) Heart

Explanation

Solution: The sound lub-dub lub-dub is produced by heart.

[#965] Blood is red in colour due to the presence of ________
Correct Answer

(D) Haemoglobin

Explanation

Solution: Hemoglobin is iron-containing oxygen transport protein in the red blood cells of all vertebrates. It has an oxygen binding capacity and gives the red colour to the blood.