Biology

Human Immunity and Blood

2,051 Questions

Human immunity and blood questions cover the physiological mechanisms protecting the body against diseases and the components of blood. Topics include blood groups, cell mediated immunity, monoclonal antibodies, and blood coagulation. These biology topics frequently appear in general science sections of competitive exams.

Blood groupsCell mediated immunityMonoclonal antibodiesBlood coagulationCancer immunology

Human Immunity and Blood Questions

Multiple choice

Match the following:

 
a. Plasma B - cells 1. They produce more B-lymphocyte cells.
b. Memory B - cells 2. They secrete antibodies into the blood circulation.
c. Dividing B - cells 3. They do not produce antibodies, but become programmed to remember a specific antigen and
respond very rapidly to any subsequent infection.

  1. a - 2, b - 1, c - 3

  2. a - 3, b - 2, c - 1

  3. a - 1, b - 2, c - 3

  4. a - 1, b - 3, c - 2

  5. a - 2, b - 3, c - 1
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is the correct option.  This is a wrong option. 

Multiple choice

The fluid part of the blood is called

  1. plasma

  2. platelets

  3. lymph

  4. RBC
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Blood is a fluid flowing in blood vessels. It has its several components. Its several components are plasma, red blood cells, white blood cells and the platelets. The fluid part of the blood is known as plasma. Blood is red in colour due to the presence of a pigment called haemoglobin.

Multiple choice

Which process helps in the healing of wounds?

  1. Erythropoiesis

  2. Blood clotting

  3. Haemolysis

  4. Agglutination
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

If there is any cut or wound, the platelets of blood reach the surface and plug in the wound by clotting blood at that place. Therefore, platelets help in the healing of wounds by blood clotting.

Multiple choice

Lymph differs from the blood as it has

  1. more WBC's and few RBC's

  2. only WBC's and no RBC's

  3. more RBC's and few WBC's

  4. only RBC's and no WBC's
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Lymph is a pale fluid made up of only WBCs and not RBCs. So, option 2 is correct.

Multiple choice

The universal acceptor blood group is

  1. A Group

  2. B Group

  3. AB Group

  4. O Group
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

AB blood group is called the universal acceptor because individuals with AB blood have both A and B antigens on their red blood cells but no anti-A or anti-B antibodies in their plasma. This means they can receive blood from any group (A, B, AB, or O) without having an adverse reaction.

Multiple choice

Total No. of Blood Groups in the human body are

  1. Two

  2. Three

  3. Four

  4. Five
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The ABO blood group system classifies human blood into four main types: A, B, AB, and O. These groups are determined by the presence or absence of A and B antigens on red blood cells. This is the primary and most well-known blood classification system used worldwide.

Multiple choice

A person of blood group AB can give blood to

  1. 'A' and 'B'

  2. Only 'AB'

  3. 'A', 'B' and 'O'

  4. All of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A person with blood group AB has both A and B antigens on their red blood cells, but no anti-A or anti-B antibodies in their plasma. This means they can receive blood from any group (A, B, AB, or O) - they are 'universal recipients.' However, they can only donate to other AB individuals because their blood contains both antigens. Donating to A, B, or O would trigger antibody reactions in those recipients.

Multiple choice

Which of the following blood cells help in blood clotting?

  1. Platelets

  2. Red blood cells

  3. White blood cells

  4. None of these

  5. NA
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Platelets, also known as thrombocytes, are involved in blood clotting. They adhere to the damaged blood vessels and thromboplastin is liberated from an injured tissue. Hence, it is the correct answer.

Multiple choice

Superantigens are toxins produced by many pathogenic bacteria and viruses. Which of the following statements regarding superantigens is FALSE?

  1. Staphylococcal toxic shock syndrome is an example of superantigen associated disease.

  2. Superantigen associated diseases are characterized by markedly elevated circulating levels of pro-inflammatory cytokines.

  3. In humans, a superantigen reacts with approximately 1 in 50 T-cells.

  4. Superantigens activate large numbers of B-cells.

  5. The first bacterial SAg was isolated by Bergdoll.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Superantigens simultaneously activate large numbers of T-cells carrying a particular T-cell receptor Vβ gene, by binding at a site distinct from the antigen-binding groove. Since there are 50 different Vβ genes in humans, a superantigen will react with approximately 1 : 50 T-cells in contrast to a conventional peptide antigen that will react with 1 : 104 to 1 : 108 T-cells. They do not react with the BCR.

Multiple choice

Mycobacterium is a genus characterized by various pathogenic bacteria. Granuloma formation in mycobacterial infection does NOT include which of the following processes?

  1. Engulfment of the mycobacteria by the macrophages

  2. Replication of the mycobacteria within the phagosomes

  3. Production of IL-12 to drive Th1 differentiation of immature CD4 cells

  4. TNF-α production for activation of macrophages to epithelioid forms

  5. Production of IL-4
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Production of IL-4 by Th2 cells is not a part of granuloma formation, which involves Th1 activation rather than Th2 activation.