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

In the ABO type blood system, the universal blood donor(s) is/ are

  1. A

  2. B

  3. AB

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

Since, type O blood normally lacks both A and B antigens, it will not be recognized as an alien type by the blood of anyone. As a result, anyone usually can be transfused with O blood without concern about rejection for this blood group.

Multiple choice

Which blood group person has two types of antibodies in blood?

  1. Blood group A

  2. Blood group B

  3. Blood group O

  4. Blood group AB

  5. Blood group ABO
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Blood group O individuals do not have either A or B antigens on the surface of their RBCs, but their blood serum contain IgM anti A antibodies and anti B antibodies against the A and B blood group antigens. Therefore, an individual of blood group O can receive blood only from a blood group O individual, but can donate blood to individuals of any ABO blood group.

Multiple choice

The immune cells present in the lymphatic system to protect our body from foreign particles are called ____________.

  1. erythrocytes

  2. leucocytes

  3. thrombocytes

  4. lymphocytes

  5. platelets
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

They are white blood cells present in the vertebrate immune system. The three major types of lymphocytes are T cells, B cells and natural killer (NK) cells. T cells are involved in cell mediated immunity,whereas B cells are primarily responsible for humoral immunity. NK cells help in defending the host from both tumors and virally infected cells.

Multiple choice

Antibodies are produced by

  1. R.B.C.

  2. W.B.C.

  3. both 1 and 2

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

Antibodies are produced by specialised white blood cells called B lymphocytes (or B cells). When an antigen binds to the surface of a B-cell, it stimulates the B cell to divide and mature into a group of identical cells called a clone.

Multiple choice

Type 'O' is a universal donor because it has _____.

  1. no antibodies

  2. antibodies in diluted form

  3. no antigens

  4. no white blood cells
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Type O blood lacks both A and B antigens on red blood cells, making it compatible with all other blood types. Universal donors can give to anyone because recipient antibodies won't attack O cells. Type O has both anti-A and anti-B antibodies in plasma, but the absent RBC antigens are what matters for donation.

Multiple choice

Persons with group AB are known as universal acceptors because _____.

  1. they are weak persons and always need blood transfusion

  2. the blood of all other groups can be transfused into them without any harm

  3. they have very less quantity of blood

  4. they can undergo AB blood transfusion
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Blood type AB lacks both anti-A and anti-B antibodies in plasma, allowing it to receive blood from any group (A, B, AB, or O) without antibody-mediated rejection. Universal acceptors can receive from all donors because their immune system won't attack any blood type antigens. Option A and C are false descriptions, and D merely restates the blood type.

Multiple choice

Which of the following is the largest wandering phagocytic cell of vertebrate blood?

  1. Thrombocyte

  2. Monocyte

  3. Erythrocyte

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

Monocytes are the largest white blood cells (leukocytes) in vertebrate blood. They are highly phagocytic and can migrate out of blood vessels into tissues to become macrophages, where they engulf pathogens and cellular debris. Thrombocytes (platelets) are cell fragments involved in clotting, erythrocytes (RBCs) carry oxygen, and amoebocytes are invertebrate defense cells.