variation and selection- key terms Flashcards
Define Variation
differences between individuals of the same species
Both genetic and environmental factors cause phenotypic variation
Define Continuous Variation
results in a range of phenotypes between two extremes; examples include body length and body mass
Define Discontinuous Variation
results in a limited number of phenotypes with no intermediates (e.g. ABO blood groups, seed shape in peas and seed colour in peas)
Define mutation
A genetic change.
Define Gene Mutation
a change in the base sequence of DNA
Define Adaptive Feature
an inherited (structural) feature that helps an organism to survive and reproduce in its environment
Define Xerophytes
live in deserts where water is scarce, and evaporation is rapid or in windy habitats.
Define Hydrophytes
live wholly or partly submerged in water.
Define Artificial Selection
breeds organisms with valued characteristics together to produce offspring that share those valuable characteristics.
Define adapation
the process of natural selection by which populations become more suited to their environment over many generations.