variation in phenotype Flashcards
what is a mutation
sudden changes to genes and chromosomes may be passed on to the next generation which is the main source of variation
what is meiosis
special form of nuclear division which produces new combinations of alleles before they are passed into gametes which are all different
what is random fertilisation
in sexual reproduction this produces new combination of different allele and offspring’s therefore different from parents
when can bar charts be used in variation
variation largely due tp genetic factors fit into a few distinct categories where there are no intermediate species for example the abo blood group system
how does the environment influence variation
the gene sets the limits but the environment determines where the organism lies within those limits
how are the variation expresse as data
they may merge and grade into one another forming a continuum and they are not controlled by a certain gene but are polygenetic so we see a bell shaped distribution curve
why is it difficult to produce conclusion about variation
it is difficult to distinguish the affects of may genetic and environmental influences that combine to produce differences between individuals
