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 zoology diseases and immunity innate and acquired immunity body fluids and immune responses immunity and immune system

Immunomodulators 

  1. Stimulates immune system

  2. Suppress immune system

  3. Some stimulate ,others inhibit immune system

  4. Never suppress immune system
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Immunomodulation is modulation (regulatory adjustment) of the immune system. Homeostasis in the immune system, whereby the system self-regulates to adjust immune responses. Immunomodulators are a part of immunotherapy, in which immune responses are induced, amplified, attenuated, or prevented according to therapeutic goals.

So, the correct answer is 'Some stimulate, others inhibit the immune system'.

Multiple choice zoology diseases and immunity innate and acquired immunity body fluids and immune responses immunity and immune system

Non-specific immunity is provided by all except ________________.

  1. Kupffer cells

  2. alveolar macrophases

  3. lymphocytes

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

Non-specific (innate) immunity includes physical barriers and phagocytes like Kupffer cells, alveolar macrophages, and neutrophils. Lymphocytes (T and B cells) are the primary components of specific (adaptive) immunity.

Multiple choice zoology diseases and immunity innate and acquired immunity body fluids and immune responses immunity and immune system

Which one of the following is mismatched

  1. Helper T-cells-help complement react

  2. Memory T-cells-long-living line of 1-cells

  3. Suppressor T-cells-shut down the immune response

  4. Cytotoxic T-cells-active in tissue rejection
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A- Helper T cells are arguably the most important cells in adaptive immunity, as they are required for almost all adaptive immune responses. They not only help activate B cells to secrete antibodies and macrophages to destroy ingested microbes, but they also help activate cytotoxic T cells to kill infected target cells.

B- However, a small portion of long-lived T cells still remains for rapid response upon pathogen re-exposure. This kind of cells is called memory T cells. Because memory T cells have been trained to recognize specific antigens, they will trigger a faster and stronger immune response after encountering the same antigen. This is how vaccines work to protect us against infection.
C- Suppressor T cells are sensitive to high concentrations of circulating lymphokine hormones, and release their own lymphokines after an immune response has achieved its goal. This signals all other immune-system participants to cease their attack. Some memory B-cells remain after this signal to ward off a repeat attack by the invading organism.
D- A cytotoxic T cell (also known as TC, cytotoxic T lymphocyte, CTL, T-killer cell, cytolytic T cell, CD8+ T-cell or killer T cell) is a T lymphocyte (a type of white blood cell) that kills cancer cells, cells that are infected (particularly with viruses), or cells that are damaged in other ways.

So, the correct option is 'option A'.

Multiple choice zoology diseases and immunity innate and acquired immunity body fluids and immune responses immunity and immune system

Which of the following is not related with thymosins?

  1. In addition to cell mediated immunity thymosins also promote production of antibodies to provide humorala immunity

  2. In old age,thymosins production is more so immunity is strong

  3. Thymosins are produced by thyroid gland

  4. Both B and C
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The hormone that is released from the thymus is called thymosin. They are involved in the synthesis of T-cells. Hence, these hormones are involved in cell-mediated immunity. They also modulate the production of antibodies in a person. The thymus reduces in size with age and so does the release of thymosin. Thymosin has also been reported to be released from some other organs.
So, the correct answer is 'B, In old age, thymosins production is more so immunity is strong'.
Multiple choice zoology diseases and immunity innate and acquired immunity body fluids and immune responses immunity and immune system

The ability of the body's immune system to recognize its own tissues is known as

  1. Immunologic tolerance

  2. Autoimmunity

  3. Severe combined immunodeficiency disease

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

Immunologic tolerance is the state of unresponsiveness of the immune system to substances or tissues that have the potential to induce an immune response. Self-tolerance to individuals own antigen is achieved through central and peripheral tolerance.

So, the correct option is 'Immunologic tolerance'.

Multiple choice bio-chemistry immunology innate and acquired immunity body fluids and immune responses immunity and immune system

Which of the following is not a part of the inflammatory response

  1. Antibodies

  2. Swelling

  3. Redness

  4. Presence of histamine
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Inflammation, a response triggered by damage to living tissues. The inflammatory response is a defence mechanism that evolved in higher organisms to protect them from infection and injury. Its purpose is to localize and eliminate the injurious agent and to remove damaged tissue components so that the body can begin to heal. The four cardinal signs of inflammation—redness (Latin rubor), heat (calor), swelling (tumor), and pain (dolor).


So, the correct option is 'Antibodies'.

Multiple choice bio-chemistry immunology innate and acquired immunity body fluids and immune responses immunity and immune system

Which of the following is not characteristic of the early stages of a localized inflammatory response?

  1. Increased permeability of capillaries

  2. Attack by cytotoxic T-cells

  3. Release of histamine

  4. Dilatation of blood vessels
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Inflammation is a very prominent response to TNF-α. There are four typical signs of inflammation, erythema (redness), heat, swelling, and pain. These are a consequence of increased blood flow and capillary permeability, the influx of phagocytic cells, and tissue damage. Increased blood flow is caused by constriction of the capillaries that carry blood away from the infected area, and leads to engorgement of the capillary network. Erythema and an increase in tissue temperature accompany capillary constriction. In addition, the permeability of capillaries increases, allowing cells and fluid to leave and enter the surrounding tissue. These fluids have a higher protein content than the fluids normally found in tissues, causing swelling.


So, the correct option is 'Option B'.

Multiple choice bio-chemistry immunology innate and acquired immunity body fluids and immune responses immunity and immune system

Histamine released by the lymphocytes causes inflammatory response

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

One of the best-known chemical mediators released from cells during inflammation is histamine, which triggers vasodilation and increases vascular permeability. Stored in granules of circulating basophils and mast cells, histamine is released immediately when these cells are injured.


So, the correct option is 'True'.

Multiple choice bio-chemistry immunology innate and acquired immunity body fluids and immune responses immunity and immune system

In the inflammatory response, the absence of which one of the following would prevent all the others from happening?

  1. Release of histamine

  2. Dilatation of arterioles

  3. Increased population of phagocytes in the area

  4. Increased permeability of blood vessels
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Histamine, biologically active substance found in a great variety of living organisms. It is distributed widely. The effect histamine has on blood vessels is crucial to its role in the immune response, which is most clearly observed in inflammation i.e., the local reaction of bodily tissues to injury caused by physical damage, infection, or allergic reaction. Injured tissue mast cells  release histamine, causing the surrounding blood vessels to dilate and increase in permeability. This allows fluid and cells of the immune system, such as leukocytes (white blood cells) and blood plasma proteins, to leak from the bloodstream through the vessel walls and migrate to the site of tissue injury or infection, where they begin to fight the infection and nourish and heal the injured tissues..


So, the correct option is 'Option A'.

Multiple choice bio-chemistry human body and organ system role of blood in transport function of blood blood and lymph body fluid

Blood protects the body from infections and diseases with the help of

  1. WBCs

  2. RBC

  3. Platelets

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

Blood performs the important task of protecting the body from the infections and disease-causing bacteria. The white blood cells found in blood are responsible for safeguarding the different organs of the body by producing antibodies and proteins which are capable of fighting off and killing the germs and viruses that cause serious damage to the body cells. The platelets present in blood handle the task of limiting blood loss in the wake of an injury by helping the blood to clot quickly. 

Multiple choice biology digestion and absorption digestive system- glands mouth and buccal cavity digestive glands

Deoxygenated blood is processed by

  1. Hepatocytes

  2. Neurocytes

  3. Lymphocytes

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

  • The liver receives blood supply from two sources. 
  • The first is the hepatic artery which delivers oxygenated blood from the general circulation. 
  • The second is the hepatic portal vein delivering deoxygenated blood from the small intestine containing nutrients. Hence, Deoxygenated blood is processed by hepatocytes.
So, the correct answer is 'hepatocytes'.

Multiple choice biology organization of life the cell structure cytoplasm number and shape of cells

RBCs are

  1. Differentiated cells.

  2. Undifferentiated cells.

  3. Dedifferentiated cells.

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

Mammalian erythrocytes also called as red blood cells are formed in bone marrow from multipotential hemocytoblast and further converted to erythroblast (normoblast). The nucleus and mitochondria of erythroblast disappear and it is converted to mature erythrocyte with haemoglobin. So RBC's are differentiated cells which lack a nucleus.