The Human defense System Flashcards
What is the purpose of the human defence system?
To protect against pathogens, organisms that may cause disease.
Human immunity refers to our ability to _______.
resist disease.
What is the first line of the general defence system?
Skin, blood clotting, mucous, acid, and lysosome.
How does the skin contribute to the human defence system?
Provides a structural barrier against pathogens.
What role does blood clotting play in the defence system?
Forms a barrier against the entry of pathogens if the skin is broken.
What is the function of mucus in the nasal passages?
Traps dust and microorganisms before they are swallowed.
What is the role of hydrochloric acid in the stomach?
Kills many pathogens.
Where is lysosome found and what does it do?
Found in sweat, tears, and saliva; attacks and dissolves the cell walls of bacteria.
What is the second line of the general defence system?
Phagocytosis and defence proteins.
What is phagocytosis?
Process by which white blood cells engulf and destroy pathogens.
What attracts white blood cells to sites of injury and infection?
Chemical messengers.
What are large phagocytes called?
Macrophages.
What are defence proteins mentioned in the defence system?
Complement and interferons.
What do defence proteins do?
Destroy viruses and other proteins.
What is the specific defence system responsible for?
Production of antibodies and destruction of infected body cells.
What type of cells destroy infected body cells in the specific defence system?
Specific white blood cells (WBCs).
White blood cells (leucocytes) can be subdivided into _______ and _______.
lymphocytes; monocytes.
What is the function of lymphocytes in the immune response?
Produce antibodies or directly destroy infected cells.
Where do lymphocytes and monocycles migrate to?
The Spleen and thymus gland
What is the first function of lymphocytes?
Attack body cells that have antigens on their surface
What is the second function of lymphocytes?
To produce antibodies to clump pathogens together
Define the term immunity
The ability to resist disease
What is Induced Immunity
The ability to resist disease caused by specific pathogens by the production of antibodies
What 2 forms does Induced immunity have
Active and Passive
What is Active immunity?
The production of antibodies by the body in response to the entry of pathogens
What 2 forms can Active immunity be divided into
Natural and Artificial
What is Natural active immunity
Occurs when a pathogen enters the body in a normal way
What is artificial active immunity
Occurs when a vaccine is introduced into the body
What is passive immunity
The giving of antibodies formed by another organism
What is natural passive immunity
Child receiving antibodies from its mother in breast milk
What is Artificial Passive immunity
Person receives an injection containing antibodies produced by another organ
What 2 forms do WBC have
Lymphocytes or monocytes
What cells can Lymphocytes be
T or B cells
Where are T and B cells produced
Bone marrow
When mature, Where do B cells move into?
The spleen and lymph nodes
When an antigen is ingested into the pathogen what is it called?
microphage
How do B cells fight a specific antigen
It quickly multiplies allowing it to produce large quantities of antibodies
What happens to B cells after pathogens have been killed
Most of them die while some remain as recovery B cells
What do Memory B cells ensure if a pathogen is detected again?
Antibodies are produced in much smaller quantities in response
Antibodies are produced quicker
What do T cells act against?
Viruses and cancer cells
What do Rampoging macrophages injest
Pathogens or infected cells
What are the 4 types of T cells
Helper T cells (recognize antigens and produce cytokines)
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White T cells (Attack and destroy abnormal body cells and release perforin)
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Hille T cells (Bring about apoptosis or programme cell death)
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Supressor T cells ( Become active after pathogen has been destroyed)
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