Module 4 - Keywords Flashcards
Disease
A departure from good health caused by a malfunction of the mind or body which causes physical, mental or social symptoms
Pathogens
Organisms that cause disease
Parasites
Organisms that live in or on another living thing (host), causing it harm
Transmission
The way in which a pathogen or parasite travels from one host to another
Immune response
The specific response to antigens on the cell surface membrane of a pathogen. It involves lymphocytes and the production of antibodies
Primary defences
Prevent pathogens from entering the body
Secondary defences
Attempt to kill pathogens after they have entered the body
Non specific
Digest a range of pathogens
Antigens
Protein/glycoprotein found on the cell surface membrane on cells. Foreign antigens stimulate an immune response
Antibodies
Proteins which identify and neutralise antigens. Each antibody is specific to a particular antigen due to the complementary shape of the antigen and the variable region of the antibody
Vaccination
A deliberate exposure to antigenic material which activates the immune system to make an immune response and provide immunity
Natural immunity
Gained in the normal course of living
Artificial immunity
Gained by an injection which is a deliberate exposure to antibodies or antigens
Passive immunity
Acquired without the activation of the lymphocytes - provided by antibodies that have not been made by the person’s own immune system
Active immunity
Acquired by the activation of the person’s own immune system
Biodiversity
The range of habitats, the number of different species and their relative abundance, and the genetic diversity within a species within an area. It takes into account species richness and species evenness
Habitat biodiversity
The range of habitats in which different species live
Species biodiversity
The number of different species living in a habitat (species richness) and their relative abundance ( species evenness )
Genetic biodiversity
Variation between individuals of the same species
Species richness
The number of different species in a habitat
Species evenness
Relative numbers of how many individuals in each species
Locus
The position of the gene on the chromosome
Species
A group of organisms similar in appearance, physiology and genetics whose members are able to interbreed to produce fertile offspring.
Habitat
The place where an organism lives
Species
A group of organisms similar in appearance, physiology + genetics whose members are able to interbreed to produce fertile offspring
Extinct
No members of a species remain + it ceases to exist
Critically endangered
Likely to become extinct as the species numbers have become low due to man made or natural changes in the environment
Conservation
Maintaining biodiversity between species, genetic biodiversity within species + a variety of habitats + ecosystems
In situ conservation
Conserving a species in its normal habitat. Attempting to minimise human impact on the natural environment + protecting the natural environment + maintain biodiversity
Ex situ conservation
Conserving an endangered species by activities that take place outside its normal environment
Simpson’s index of biodiversity (D)
A measure of biodiversity as it takes into account species richness and species evenness
Classification
Process of sorting living things into groups of similar organisms. Reflects how closely related they are and evolutionary relationships
Taxonomy
The study of the principles behind classification - the study of the differences between species (physical and genetic)
Phylogeny
The study of the evolutionary relationships between organisms, the study of how closely related they are
Variation
Differences within a species or between different species
Adaptation
A feature that enhances survival and long-term reproductive success
Natural Selection
‘Selection’ by the environment of individuals that show certain favourable variations. These individuals will survive to reproduce and pass on their variations to the next generation
Evolution
The gradual change in the characteristics of a species over many generations. Driven by selective pressure and natural selection
Speciation
The formation of a new species from a pre-existing one
Selective pressure
An external factor that drives evolution in a particular direction. It might cause competition between individuals or cause some organisms to die whilst others survive
