Biology

Human Immunity and Blood

2,096 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

Monoclonal antibodies are ____________________.

  1. antibodies that can be used only once

  2. non-functional antibodies

  3. antibodies produced by hybridoma technique

  4. antibodies involved in auto-immunity
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Monoclonal antibodies are antibodies produced by hybridoma technique.

Multiple choice

The human body contains the maximum amount of

  1. Plasma

  2. Cytoplasma

  3. Water

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

Water constitutes about 60% of the adult human body by weight, varying from 55-75% depending on factors like age, gender, and body composition. Plasma is part of blood, cytoplasm is within cells (mostly water), and proteins are macromolecules. Water is the single largest component, essential for all physiological processes.

Multiple choice

Which is the most common blood group among the Asians?

  1. A

  2. B

  3. AB

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

Blood group B is the most prevalent among Asian populations, particularly in East Asia. Group A (A) is common in Europe, Group AB (C) is the rarest worldwide, and Group O (D) is universal but not the most common in Asia specifically. Distribution varies by ethnicity and geography.

Multiple choice

Human erythrocytes are formed from precursor stem cells called

  1. hemocytes

  2. hemocytoblasts

  3. erythropocytes

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Hemocytoblasts (pluripotent hematopoietic stem cells) are the precursor cells that give rise to all blood cells, including erythrocytes (red blood cells). Hemocytes and erythropocytes are not the correct precursor cell names.

Multiple choice

Which one of the following statements relating to ‘rheumatoid factor’ is true?

  1. The finding of rheumatoid factor in a given patient's blood is a diagnosis of rheumatoid arthritis.

  2. Rheumatoid factor is a poor prognostic factor when found in patients with rheumatoid arthritis.

  3. Rheumatoid factor is an IgE molecule.

  4. Rheumatoid factor can form immune complexes with IgE.

  5. Rheumatoid factors are always found transiently in the blood of patients who have recently suffered from an infection.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Rheumatoid factor does indicate a poor prognosis when found in RA patients, correlating with extra-articular (non-joint) complications of RA such as nodules, lung disease and vasculitis as well as with severely affected joints.

Multiple choice

Which among the following cells instructs B cells and T cells to specific regions within the lymphatic tissue of an individual?

  1. A fibroblast

  2. A fibrocyte

  3. A reticular cell

  4. A tendon cell

  5. A mast cell
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A reticular cell is a type of fibroblast that synthesises type III collagen and uses it to produce reticular fibers. Reticular cells are found in many tissues including the spleen, lymph nodes and lymph nodules. They also direct B cells and T cells to specific regions within the lymphatic tissue.

Multiple choice

Which one of the following statements is true regarding the removal of cells by apoptosis?

  1. Auto-antigens are frequently methylated and this results directly in autoimmune sensitisation

  2. C5 plays a central role in cellular clearance

  3. Apoptosis can also be mediated by T cells using FAS:FAS ligand interactions

  4. Nuclear material is expanded beneath a blebbed membrane

  5. Macrophages secrete the pro-inflammatory cytokines IL-10 and TGFβ in response to cellular ingestion
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Fas ligand (CD178) is expressed on activated T cells. The interaction with FAS which is a protein on many cell types triggers enzymes to degrade the target cell DNA.

Multiple choice

The ABO blood group system classified blood into

  1. Four types

  2. Two types

  3. One type

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

The ABO blood group system classifies human blood into four main types based on the presence or absence of A and B antigens: Type A (A antigen only), Type B (B antigen only), Type AB (both antigens), and Type O (neither antigen). This classification system is fundamental for safe blood transfusion.

Multiple choice

Which blood group is known as the a universal donor?

  1. A

  2. B

  3. AB

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

Blood type O, particularly O-negative, is called the universal donor because individuals with this blood type can donate red blood cells to people with any other blood type (A, B, AB, or O). This is possible because O-type blood lacks A and B antigens on red blood cells that would trigger an immune response. Blood types A, B, and AB each have specific antigens that make them incompatible with universal donation. The 'a' in the question appears to be a typo.