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

Find the correct descending order of percentage proportion of leucocytes in human blood

  1. NeutrophiIs $\rightarrow$ Basophils $\rightarrow$ Lymphocytes $\rightarrow$ Acidophils $\rightarrow$ Monocytes
  2. Neutrophils $\rightarrow$ Monocytes $\rightarrow$ Lymphocytes $\rightarrow$ Acidophils $\rightarrow$ Basophils
  3. Neutrophils $\rightarrow$ Lymphocytes $\rightarrow$ Monocytes $\rightarrow$ Acidophils $\rightarrow$ Basophils
  4. Neutrophils $\rightarrow$ Acidophils $\rightarrow$ Basophils $\rightarrow$ Lymphocytes $\rightarrow$ Monocytes.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The standard mnemonic for leukocyte abundance is Never Let Monkeys Eat Bananas: Neutrophils (60-70%), Lymphocytes (20-25%), Monocytes (3-8%), Eosinophils/Acidophils (2-4%), and Basophils (0.5-1%).

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

Which one is agranulocyte?

  1. Basophil

  2. Eosinophil

  3. Lymphocyte

  4. Neutrophil
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation
White blood cells or leucocytes can be granular or agranular depending upon whether they have granules or not.
Granulocytes are granular leucocytes and are of three types:
  • Eosinophils- These cells play important role in immunity and allergic reactions.
  • Basophils- These cells secrete histamine, serotonin and heparin.
  • Neutrophils- These cells perform phagocytosis.
Agranulocytes are non-granular leucocytes and are of two types:
  • Lymphocytes- These cells produce antibodies.
  • Monocytes- These cells are phagocytic.
So, the correct answer is 'Lymphocyte'.
Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

In terms of descending order of percentage proportions of leucocytes in human blood, which one is correct? 

  1. Neutrophils $\to$ lymphocytes $\to$ monocytes $\to$ acidophils $\to$ basophils
  2. Neutrophils $\to$ basophils $\to$ lymphocytes $\to$ acidophils monocytes
  3. Neutrophils $\to$ monocytes $\to$ lymphocytes $\to$ acidophils $\to$ basophils
  4. Neutrophils $\to$ acidophils $\to$ basophils $\to$ lymphocytes $\to$ monocytes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
 Cells   Percentage proportion of total leucocyte count  $Cells/mm^3$ of blood
Cells 
Percentage proportion of total leucocyte count
Neutrophils 60-70%   4000-5000 cells/$mm^3$
60-70%
Lymphocytes  20-40%  1500-2500 cells/$mm^3$
Monocytes  2-7%  200-700 cells/$mm^3$
Acidophils  1-5%  70-300 cells/$mm^3$
Basophils 0.5-2.7% 35-150 cells/$mm^3$
0.5-2.7%

Thus, the correct answer is (A).

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

Select the incorrect statements
I. Barr body is an another name for neutrophilis
II. Agranulocytes are formed in the red bone marrow
III. Granulocytes are formed is the spleen and lymph node
IV. Lymphocytes exists as two major types, B and T lymphocytes
The correct option with incorrect statements is

  1. I, II and III

  2. Only I

  3. Only III

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

I.Barr body is an another name of neutrophilis is false – because Barr body is a inactive X chromosome.

II.Agranulocytes are formed in the red bone marrow – False, because, they are  formed from the bone marrow of the human being

III.Granulocytes are formed in the spleen and lymph node – False, because granulocytes are formed from myeloid stem cells

IV.Lymphocytes exists as two major types, B and T lymphocytes – True.

So, the correct option is ‘I, II and III’.

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

In a healthy adult man, the commonest and smallest type of leucocytes are

  1. Basophils

  2. Monocytes

  3. Eosinophils

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

Lymphocytes are the smallest leukocytes with a rounded nucleus. They flow through the lymphatic system or fluid and consist of Natural killer cells, B-Lymphocytes and T-lymphocytes and defend the body against pathogens and infections.

So, the correct answer is 'Lymphocytes'

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-nudeated

  2. Its deficiency causes cancer

  3. Manufactured only in thymus

  4. Can squeeze through blood capillaries
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Lymphocytes a type of WBC or Leukocyte can squeeze through the walls of the capillaries into the interstitial fluid to the site of infection,  or in response to inflamation by a process called as diapedesis.

So, the correct answer is 'Can squeeze through blood capillaries'

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

A type of white blood cell with a very large nucleus, rich in DNA, and a small amount of clear cytoplasm, is found in the blood. It produces antibodies and is important in defence against disease. Name it. 

  1. Lymphocyte

  2. Myeloid cell

  3. Fibroblast

  4. Neutrophil
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
Lymphocytes are one of several different types of white blood cells. Each type of white blood cell has a specific function, and they all work together to fight illness and disease. White blood cells are an important part of the immune system. The bone marrow constantly produces cells that will become lymphocytes. Some will enter the bloodstream, but most will move through the lymphatic system. The lymphatic system is the group of tissues and organs, like the spleen, tonsils, and lymph nodes, that protect your body from infection.
So the correct option is 'lymphocyte'.
Multiple choice evs our body- its internal organ system leucocytes body fluids and immune responses respiratory and circulatory system

Which one is smallest?

  1. Eosinophil

  2. Basophil

  3. Neutrophil

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

A.Eoisinophil - These cells are 10 - 15 µm in diameter

B.Basophils - They are 14-16 µm in diameter, 

C.Neutrophil – The cells are 12 to 17 µm in diameter

D.Monocyte – The cells are 15 to 30 µm in diameter.

So, the correct option is ‘Eosinophils’.

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

Migration of phagocytes and other leucocytes towards the place of infection occurs through

  1. Thromnosis

  2. Diapedesis

  3. Emboly

  4. Phagocytosis
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
When a tissue is damaged or any infection occurs the phagocytes and other leucocytes move out of the circulatory system through the intact walls of the capillaries to the site of tissue injury or infection. This phenomenon is called diapedesis. Diapedesis is a part of the innate immune response.
So, the correct answer is 'Diapedesis'.