Immunity Yr 11 Bio

Pathogen

A disease-causing organism or agent

Transmissible Disease

An infectious disease where the pathogen can pass from one host to another.

Direct Contact

Transmission requiring close physical contact between hosts or contact with infected bodily fluids.

Indirect Contact

Transmission without direct physical contact

Host

The organism in which a pathogen lives and causes disease.

Body Defences

Non-specific physical barriers like skin

White Blood Cell (Leukocyte)

Immune system cells involved in defending the body against infectious diseases and foreign invaders.

Antigen

A unique molecule on a pathogen's surface that triggers a targeted immune response.

Antibody

Y-shaped proteins produced by B cells that bind to and help destroy specific antigens.

Active Immunity

Long-term defence from the body producing its own antibodies and memory cells after exposure.

Passive Immunity

Short-term defence gained by acquiring antibodies from another individual

Placenta

Organ that provides passive immunity to a fetus by transferring maternal antibodies.

Breast Milk

Provides passive immunity to infants by transferring maternal antibodies for early protection.

Memory Cell

Specialised B and T cells that remember antigens for a faster future immune response.

Macrophage

A large phagocytic cell that engulfs pathogens and presents antigens to T helper cells.

B Cell (B Lymphocyte)

A white blood cell responsible for producing and secreting highly specific antibodies.

T Helper Cell

Regulatory cell releasing chemicals to activate B cells

T Killer Cell

White blood cell that releases chemicals to directly kill infected cells and pathogens.

Phagocytosis

The process by which white blood cells engulf and digest pathogens.

Antibiotic

A chemical substance that kills or inhibits bacteria

Antibiotic Resistance

The ability of bacteria to survive antibiotic exposure due to evolutionary DNA mutations.

Vaccination

Introducing weakened or inactive pathogens to stimulate a primary immune response and memory cells.

Aseptic Technique

Procedures used to prevent contamination by unwanted microorganisms during bacterial investigations.

Fungal Infection Treatment

Treated with antifungal medications like creams or oral pills.

Bacterial Infection Treatment

Treated with antibiotics

Viral Infection Treatment

Cannot be treated with antibiotics

managed with rest

fluids

Active immunity

is long-term protection gained when the body's own immune system is stimulated by foreign antigens to produce its own specific antibodies and memory cells.

Passive immunity

is short-term protection provided by acquiring ready-made antibodies from an external source, without the recipient's immune system producing them or creating memory cells.