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 evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Which statement is true for WBC?

  1. Non-nucleted

  2. In deficiency, cancer is caused

  3. Can squeeze through blood capillaries

  4. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

WBC's are amoeboid in shape due to which they can easily squeeze through the walls of the capillaries at the site of injury by the process known as diapedesis and engulf the damaged cells by phagocytosis. They are nucleated cells and excess of WBCs causes cancer known as leukaemia. 

So, the correct answer is option C.

Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Spleen and thymus are haematopoietic for

  1. RBC

  2. WBC

  3. Platelets

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
Haematopoiesis is the process of formation of blood cellular components. Blood cell formation takes place in yolk sac in developing embryo. As development proceeds, blood formation occurs in liver, spleen and lymph nodes. In spleen and thymus, 20-30% of WBCs are formed while RBCs and platelets are formed in the bone marrow.  All cellular blood components are derived from haematopoietic stem cells.
Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Which is the correct sequence of arrangement of types of WBC in decreasing order in terms of number per ${mm}^{3}$ of human blood?

  1. Eosinophils --> Basophils --> Neutrophils

  2. Basophils --> Eosinophils --> Neutrophils

  3. Neutrophils --> Eosinophils --> Basophils

  4. Eosinophils --> Neutrophils --> Basophils
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Percentage distribution of leukocyte are as follows:

Neutrophils- 60 - 70%
Lymphocytes- 20 - 30%
Monocytes- 2 - 8%
Eosinophils- 1 - 4%
Basophils- 0.5 - 1%
Thus, the correct answer is option C.

Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Which blood cells of mammals are concerned with immunity?

  1. Young Erythrocytes

  2. Leucocytes

  3. Thrombocytes

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

Leucocytes or the white blood cells are concerned with immunity. They perform phagocytosis, antigen-presenting, the release of antibodies, release of cytokines, opsonization etc. to keep the immunity of the body against the pathogens. Erythrocytes or the red blood cells are responsible for the transportation of oxygen. Thrombocytes or the platelets are responsible for blood clotting.

Hence, the correct answer is 'Leucocytes'.

Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

WBC is called as true cell because of

  1. Presence of nucleus

  2. Phagocytosis

  3. Polymorphism

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The components of blood consists of red blood cells, white blood cells and platelets. Of these, only white blood cells are true cells or complete cells as they have a nucleus, organelles and other cell structures and processes such as expressing proteins.
Thus, the correct answer is option (A).

Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Increase in number of leukocytes beyond normal indicates

  1. Anaemia

  2. Infection

  3. Increased defence against pathogen

  4. Non-formation of RBC.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A high white blood cell(leukocyte) count isn't a specific disease, but it can indicate another problem, such as infection, stress, inflammation, trauma, allergy, or certain diseases. That's why a high white blood cell count usually requires further investigation.


So, the correct answer is 'Infection'.

Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Number of leucocytes present in one $mm^3$ of blood is

  1. 5000-8000

  2. 2000-3000

  3. 8000-13000

  4. 1 million to 1.5 million
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Leucocytes or white blood cells (WBCs) are colourless, nucleated and motile cells of blood.. Their normal count is 5000- 8000 cells per mm3 of blood. WBCs (White blood cells) can be granulocytes or agranulocytes.depending upon whether they have granules or not. Granular leucocytes or granulocytes are acidophils, basophils and neutrophils while agranular leucocytes or agranulocytes are lymphocytes and monocytes. All WBCs are capable of amoeboid movement with the help of which they are squeezed out of capillaries into the tissues.
So, the correct answer is '5000 - 8000'.
Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Which is correct about leucocytes?

  1. They are red coloured.

  2. They can cross capillaries.

  3. They are enucleate.

  4. Decrease in their number causes leukemia.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
A. Leucocytes are white blood cells (WBCs).
B. They are capable of amoeboid movement due to which they can cross or squeeze out of the capillaries into tissues and this process is known as diapedesis.
C. They are nucleated i.e. they have a nucleus.
D. Increase in their number cause leukemia which is cancer of WBCs.
Hence, only statement B is correct.
So, the correct answer is 'They can cross capillaries'.
Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Which one are granulocytes?

  1. Neutrophils, basophils, lymphocytes

  2. Eosinophils, basophils, monocytes

  3. Basophils, monocytes, lymphocytes

  4. Neutrophils, eosinophils, basophils
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

WBCs (White blood cells) can be granulocytes or agranulocytes.
Granulocytes are of three types:
  • Eosinophils: These cells play important role in immunity and allergic reactions. These make about 1 - 5% of total leucocytes.
  • Basophils: These cells contain heparin, serotonin and histamine. These make about 0.5 - 2.7% of total leucocytes.
  • Neutrophils: These cells perform phagocytosis and also destroy bacteria. These make about 60 - 70% of total leucocytes.
Agranulocytes are of two types:
  • Lymphocytes: These cells are of two types, B lymphocytes that maintain humoral immunity and T lymphocytes which maintain cell mediated immunity. These make about 20 - 40% of total leucocytes.
  • Monocytes: These cells are actively motile and phagocytic cells. These make about 2 - 7% of total leucocytes.
So, the correct answer is 'Neutrophils, eosinophils, basophils'.

Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Abnormal fall in total count of WBCs in the human blood is called

  1. Anaemia

  2. Polycythemia

  3. Leucopenia

  4. Leukaemia
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
Leucopenia is the decrease in WBCs (white blood cells) in the blood. This increases the chances of infection in body. WBCs are involved in the immunity of body and destroy foreign pathogens and particles. However, the number of WBCs may also decrease due to acute infection and this leads to weak immunity. Leucopenia have further subtypes depending upon which type of leucocytes are decreasing. There are five types of leucocytes in our body, basophils, eosinophils, neutrophils, lymphocytes and monocytes. If there is decrease in count of neutrophils, the condition is known as neutropenia. Most often, leucopenia occurs due to fall in neutrophils cells.
So, the correct answer is 'Leucopenia'.
Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Which of the following is related to leucocytes?

  1. They undergo diapedesis or squeeze through capillary walls

  2. Sudden fall in number indicates cancer

  3. Produced in thymus

  4. Enucleate
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
A. Leucocytes or White blood cells (WBCs) can squeeze out through capillary walls into the tissue and reach the site of injury. This process is known as diapedesis.
B. Sudden fall in number of leucocytes is called leucopenia and this increases the chances of infection. Cancer is caused when the number of leucocytes is increased abnormally and this condition is called leukemia (the cancer of white blood cells).
C. Leucocytes are produced in bone marrow. B cells which are a type of lymphocytes (agranular leucocytes) are also produced in spleen and lymph nodes.
D. Leucocytes contain a nucleus and hence they are nucleated.
Hence, statement A is true.
So, the correct answer is 'They undergo diapedesis or squeeze through capillary walls'.