Immune system T3 test

just the immune system

First line of Defence

First line of Defence

The initial barriers that prevents pathogens from entering the body. Examples; skin, mucous membranes, tears, and saliva

Second line of defence

The internal mechanisms that act once pathogens have entered the body. They act broadly against any pathogen rather than targeting specific invaders. Examples; phagocytes, and inflammation.

Third line of defence

also known as adaptive immunity. This involves specific immune responses tailored to specific pathogens. It “remembers” pervious infections to provide long-term protective. Examples; T cells and B cells

Physical barrier

Physical structures that prevent pathogens from entering the body. Examples; the skin, mucous membranes, and cilia

Chemical barrier

Substances that destroy or inhibit pathogens either on the body surfaces or internally. Examples; stomach acid, saliva, and enzymes in tears

Inflammation

A protective response involving immune cells, blood vessels, and molecular mediators. It aims to eliminate the initial cause of cell injury, clear out damaged cells, and initiate tissue repair.

White blood cell

Cells of the immune system that are involved in defending the body against both infectious disease and foreign invaders. There are several types, including phagocyte and lymphocytes (T and B cells)

Phagocyte

A type of white blood cell that “eats” and destroys pathogens by engulfing them. Common phagocytes include macrophages and neutrophils

Phagocytosis

a process where a cell binds to the item it wants to engulf on the cell surface and draws the item inward while engulfing around it. Often when its trying to destroy something.

T cells

A type of white blood cell that is crucial for cell-mediated immunity. They recognize and destroy infect cells, coordinate immune responses, and can “remember past infections”

B cells

A type of white blood cell that produces antibodies which target specific pathogens. They play a major role in the humoral immune response.

Memory cells

Specialized T and B cells that “remember” a specific pathogen after an infection has resolved or after vaccination. They provide rapid and robust responses upon subsequent exposures to the pathogen

Antibody

A protein produce by B cells that binds specifically to a particular substance, usually an antigen. Antibodies help neutralize or eliminate pathogens.

Antigen

A substance or molecule that is recognized by the immune system as being foreign, usually found on the surface of pathogens. It can trigger an immune response when detected

Lymphatic system

A system of vessels, nodes, and organs that transport lymph throughout the body. It plays a vital role in maintaining fluid balance, filtering harmful substances, and supporting the immune system.

lymphocyte

a type of white blood cell that is responsible for antibody production, the killing of virus infected and tumor cells, and regulation of the immune response.

Lymph

Keeps the body cells moist as well as transporting oxygen, hormones and nutrients to different parts of the body and removing metabolic waste from the cells. It transports antibodies and lymphocytes to the blood

Pathogen

An organism that wishes to cause disease to it’s host. Can be a virus, bacteria, fungi, or parasite.

Prions

a type of protein that can cause disease in animals and humans by triggering normally healthy proteins in the brain to fold abnormally. Example; Fatal Familial Insomnia and Kuru

viruses

an infectious agent that can only replicate within a host organism. Example; flu, cold

Bacteria

tiny, single-celled living organism. Can be helpful but also harmful. E-coli or Salmonella

Fungi

eukaryotic organisms that include microorganisms such as yeasts, molds, and mushrooms.

protozoa

microscopic unicellular eukaryotes that have a complex internal structure and carry out complex metabolic activities. Contain a nucleus and other cell structures (similar to plant and animal cells). Example; Malaria, Amoeba.

fever

an elevated body temperature that occurs when the is trying to kill an infection.

Parasite

an organism that lives on or in a host organism and gets its food from or at the expense of its host.

cellular pathogen

microorganisms that are composed of cells, such as bacteria and protozoa. These are able to grow and reproduce on their own.

non-cellular pathogens

microorganisms that are not composed of cells, such as viruses and prions, that are unable to reproduce or grow on their own.

host

an organism that is infected with or is fed upon by a parasite or pathogenic organism (a virus, nematode, or fungus)

endoparasite

a parasite that lives in the internal organs or tissues of its host. tape worm

ectoparasite

a parasite that lives on the skin of a host which they derive their sustenance. Tick or fleas

epidemic

a disease that affects a large number of people within a community, population, or region.

Pandemic

an epidemic that’s spread over multiple countries or continents

Active immunity

results when exposure to a disease organism triggers the immune system to produce antibodies to that disease. Can be acquired by natural immunity or vaccines.

passive immunity

provided when a person is given antibodies to a disease rather them producing them through their immune system.

vaccination

The act of introducing a vaccine into the body to produce protection from a specific disease.

ways viruses can spread

airborne, skin to skin contact, infection via contaminated food and water, infected animal bite / scratch.