variation and biodiversity Flashcards
(16 cards)
define species
species is a group of organisms which can successfully interbreed to produce fertile offspring.
explain continuous variation
a full range of intermediate phenotypes between 2 extremes (often shown by a bell curve)
explain discontinuous variation
discrete groups of phenotypes with no or very few individuals inbetween (often shown by a bar chart)
what causes variation
genes and variation
name 3 environmental factors
pH levels, pollution, weather, climate, nutrition, accidents (landslide)
how do environmental factors affect continuous variation
the environment can have a significant impact on how genes are expressed
how do environmental factors influence discrete variation
the environment has little effect as its mainly controlled by genes
where do genes come from
they’re inherited from parents
what’s an allele
variation of a specific gene
other than errors in cell division what can cause cells to mutate
radiation (uv, x-rays, ionizing radiation), chemicals (mustard gas)
what’s a good thing about mutations
-provides variation
-can increase survival due to natural selection
what’s standard deviation
sd measures the spread of data from the mean
what can the standard deviation show
-repeatability of the data
-small sd means is repeatable
what does ∑ mean
the sum of
what does x̄
mean
what are error bars
they’re bars that can be added to the graph that adds/minus the sd onto both sides of the final mean (they’re often on bar charts or line graphs)
