Immunity Vocabulary List Flashcards
Terminology Definitions (32 cards)
Define pathogen
A small organism that can cause disease. Such as bacterium, virus, prion and or a parasite.
Bacteria
Is a microscopic, unicellular (single celled) organism. The term for singular is bacterium.
Prokaryotes
Are single-celled organisms with no membranes-bound organelles (an example of this is the nucleus.). A prokaryote example is a bacteria cell.
Eukaryotes
It is the opposite to a prokaryote as it DOES contain a nucleus and membrane bound organelles.
Viruses
A virus is a small pathogen that can only be seen with a electron microscope. It is made up of infectious particles that are inactive outside a living host cell (e.g human body)
Disease
It is an unhealthy impairment of the body that prevents the body from functioning as it normally would.
Immune system
The immune system is the body’s protection/defence from infectious diseases. The system includes different cells and tissues that work as lines of defence.
Phagocytosis
It is a cellular process in which a white cell covers and ingests a cell or a large particle to break it down using enzymes.
First line of defence
-The first line of defence’s job is to prevent infection.
- It is the first point of the body that the pathogen has to get by.
Examples of first line of defence.
Skin, tears and mucous membranes.
Second line of defence
-The specialised white blood cells role is to change the shape of the pathogens membrane which allows it to surround and then ingest the dead cells and pathogens.
- This process is called phagocytosis.
Examples of second line of defence
Macrophages and Neutrophils
Third line of defence.
-Consists of two main defence groups of specialised white blood cells that are called lymphocytes (The B cells and the T cells).
Examples of third line of defence.
B cells and T cells
Non-specific immunity
-Is a general defence that reacts the same way for every infection.
-They do not have a memory of prior infections.
- Each time they carry the same intensity of reaction.
Specific Immunity
-It is targeted defence that produces antibodies to fight a specific pathogen.
-It does have memory of prior pathogens.
- Reacts harder and faster if it encounters it again.
Which of the three lines of defences are non-specific immunity?
First and Second lines of defence
Which of the three lines of defence are specific immunity?
Third line of defence.
Lymphocyte
-White blood cells in the immune system that are involved in fighting infections.
-Some lymphocytes produce antibodies.
T cells
-T=Thymus gland
-There are 25 million to a billion different T cells in our body.
-They are made in the bone marrow, but mature in the thymus.
-Type of white blood cell involved in the immune response
How many types of T cells are there?
Two: the killer T cells and the helper T cells.
Antigen
A substance that induces an immune response in the body, can be foreign or a self-antigen.
(Is a substance that triggers the production of antibodies)
Memory Cells
A type of white blood cell that is formed after exposure to a pathogen and it remembers that same pathogen in the future.
- Helps to easily fight it off next time. -It helps the response to be faster and stronger.
Vaccine
It is a chemical substance made of a dead or weakened version of a pathogen. It is then either injected or ingested to help make a person immune against that pathogen for the future.
