Immune
→ It is a complex network of organs contain cells that recognise foreign substances in the body & destroy them to protect vertebrates against pathogens.
FUNCTIONS:
→ The immune system protects your body from these infections. The immune system protects individuals in three different ways:
↳ It creates a barrier that prevents bacteria and viruses from entering the body.
↳ If a bacteria or virus does get into the body, the immune system tries to detect and eliminate it before it can reproduce.
↳ If the virus or bacteria is able to reproduce, the immune system is in charge of eliminating it.
LINES OF DEFENCE:
→ First line of defence: The body’s barriers, which include:
↳ Mechanical barriers: (e.g. intact skin & mucous membranes which protect the body against invading microorganisms).
↳ Chemical barriers: (e.g. saliva, tears, sweat, mucus & stomach acid which help to destroy microorganisms).
↳ Reflex barriers: (e.g. coughing, sneezing & blinking which help stop microorganisms entering the body).
→ Second line of defence: The body’s response to invading microorganisms:
↳ Phagocytosis: white blood cells (e.g. phagocytosis) ingest invading microorganisms and destroy them.
↳ Inflammation: response of the body to injury. Blood vessels around the injury dilate & promote blood flow to the area, bringing phagocytes to the area to ingest
microorganisms.
↳ Fever: a rise in body temperature which helps speed up the repair of tissues.
↳ Natural killer cells: directly attack invading microorganisms.
→ Third-line of defence: The action of lymphocytes & antibodies, acting directly on the invading microorganisms & provide immunity against foreign microorganisms:
↳ Inborn immunity: inherited or genetic immunity.
2 main types of immunity
↳ Acquired immunity: immunity that is built up during a persons lifetime, either through natural or artificial means.
→ Auto-immunity is the body’s inability to recognise normal tissue and thus begin to attack it. This is thought to be the cause of rheumatoid arthritis, where the
joints are destroyed by the body’s own cells.
DEFINITIONS:
→ Pathogen: → An organism that causes disease.
→ Antigen: → A molecule capable of stimulating an immune response.
→ Invader: → A foreign body that has potential to cause harm.
→ Infectious agents: → Can be viruses, bacteria, fungi, & other parasites.
→ Antibody: → AKA ‘immunoglobulin’, a protective protein produced by the immune system in response to the presence of a foreign substance (antigen).
MAJOR COMPONENTS:
→ Thymus.
→ Spleen.
→ Lymph nodes.
→ Lymph.
→ White blood cells.
→ Antibodies.
→ Hormones.
→ Bone marrow.
→ It is a complex network of organs contain cells that recognise foreign substances in the body & destroy them to protect vertebrates against pathogens.
FUNCTIONS:
→ The immune system protects your body from these infections. The immune system protects individuals in three different ways:
↳ It creates a barrier that prevents bacteria and viruses from entering the body.
↳ If a bacteria or virus does get into the body, the immune system tries to detect and eliminate it before it can reproduce.
↳ If the virus or bacteria is able to reproduce, the immune system is in charge of eliminating it.
LINES OF DEFENCE:
→ First line of defence: The body’s barriers, which include:
↳ Mechanical barriers: (e.g. intact skin & mucous membranes which protect the body against invading microorganisms).
↳ Chemical barriers: (e.g. saliva, tears, sweat, mucus & stomach acid which help to destroy microorganisms).
↳ Reflex barriers: (e.g. coughing, sneezing & blinking which help stop microorganisms entering the body).
→ Second line of defence: The body’s response to invading microorganisms:
↳ Phagocytosis: white blood cells (e.g. phagocytosis) ingest invading microorganisms and destroy them.
↳ Inflammation: response of the body to injury. Blood vessels around the injury dilate & promote blood flow to the area, bringing phagocytes to the area to ingest
microorganisms.
↳ Fever: a rise in body temperature which helps speed up the repair of tissues.
↳ Natural killer cells: directly attack invading microorganisms.
→ Third-line of defence: The action of lymphocytes & antibodies, acting directly on the invading microorganisms & provide immunity against foreign microorganisms:
↳ Inborn immunity: inherited or genetic immunity.
2 main types of immunity
↳ Acquired immunity: immunity that is built up during a persons lifetime, either through natural or artificial means.
→ Auto-immunity is the body’s inability to recognise normal tissue and thus begin to attack it. This is thought to be the cause of rheumatoid arthritis, where the
joints are destroyed by the body’s own cells.
DEFINITIONS:
→ Pathogen: → An organism that causes disease.
→ Antigen: → A molecule capable of stimulating an immune response.
→ Invader: → A foreign body that has potential to cause harm.
→ Infectious agents: → Can be viruses, bacteria, fungi, & other parasites.
→ Antibody: → AKA ‘immunoglobulin’, a protective protein produced by the immune system in response to the presence of a foreign substance (antigen).
MAJOR COMPONENTS:
→ Thymus.
→ Spleen.
→ Lymph nodes.
→ Lymph.
→ White blood cells.
→ Antibodies.
→ Hormones.
→ Bone marrow.
