variation Flashcards
(13 cards)
what may make monozygotic twins different
subsequent DNA replications/ cell divisions may introduce changes
what results in physical differences
environmental (can start in utero) and genetic variation
what’s variation called between individuals of a species
-intraspecific variation
-the greater the genetic diversity, the greater the intraspecific variation
what’s variation between different species called
-interspecific variation
-used to separate one species from another
what are some factors that influence inherited/genetic variation
-alleles
-mutations
-meiosis
-random fertilisation of gametes in sexual reproduction
how do alleles influence inherited/genetic variation
-inherit a unique combo of alleles from parents (except identical twins)
how do mutations influence inherited/genetic variation
-they lead to differences over time
how does meiosis influence inherited/genetic variation
-independent assortment and crossing over in meiosis
what are the environmental factors which influence variation
-food availability (influence weight, height, etc)
-exposure to sunlight makes person tanned and increases plant growth
-trimming plants and abiotic conditions plants exposed to
-pathogens and biotic factors
what do environmental changes effect
-which genes become active
-not all genes active at the same time (e.g. active/inactive during puberty)
what factors are influenced by both environmental and inherited/genetic variation
-height, weight, limited by genes but affected by the environment
what is continuous variation (data) a result of
the combined effects of more than one gene and the environment
what is discontinuous variation (data) the result of
a single gene not influenced by the environment
