IB Biology Sub-topic C3.2 Definitions

This page contains our IB Biology definitions for sub-topic C3.2. By learning each one of these definitions, you will fully cover the content for IB Biology 'Defence against infectious disease'.
agglutination

The destruction method involving sticking pathogens together to make phagocytosis easier

AIDS

A disease characterized by a low white blood cell count caused by HIV

allergy

A systemic reaction to a normally harmless substance, caused by basophil and mast cell oversecretion of histamine

antibiotic

A chemical produced by microorganisms that kills or controls the growth of bacteria by blocking prokaryotic cell processes and not eukaryotic ones

antigen

Surface molecules expressed on any organism or virus

bacteria and virus neutralization

The destruction method involving binding to bacteria and viruses to prevent them from binding to cells

complement activation

The destruction method involving binding to pathogens to allow complement proteins to attack the pathogen by lysis

coronary thrombosis

The occlusion of an artery by blood clots caused by the rupture of a plaque

fibrillation

The uncoordinated contraction of cardiac muscle

HIV

A infection that is notoriously difficult to treat beause it infects lymphocytes involved in antibody production and can destroy them over time, preventing antibody production

hybridoma cell

A cell that was formed from the fusion of a myeloma and memory cell

long term immunity

The ability of memory cells to produce antibodies at a higher rate and quantity when an antigen is encountered again

macrophage

A white blood cell involved in the non-specific immune response that ingests pathogens via phagocytosis and presents its antigen to a specific T-helper cell

memory cell

A B cell clone that stays in the body after plasma cells have degraded and provide long term immunity

monoclonal antibodies

Identical antibodies produced by hybridoma cells

myeloma cell

A type of tumor cell

neutralization

The destruction method involving binding to toxins produced by pathogens to minimize their effect

non-specific immunity

An immune response lead by phagocytes that consumes any pathogen that enters the body

opsonization

The destruction method involving binding to pathogens and labelling them for phagocytes

pathogen

An organism or virus that causes a disease

phagocytosis

The endocytosis of pathogens by phagocytes

plasma cell

A B cell clone with a large rough endoplasmic reticulum to produce antibodies against the presented antigen

platelets

Small cell fragments that circulate in the blood and involved in clotting

specific immunity

An immune response lead by lymphocytes that produces antibodies to specific pathogens that enters the body

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