[18.2] variation in phenotype
No description yet. This curated deck is ready for daily study.
Card preview (8)
what causes variation? (3)
• genetics • environment • epigenetics
how might genetics cause variation? (3)
• mutations • meiosis • random fertilisation of gametes
how might environment cause variation? (2)
• food availability • prevailing wind can affect direction of tree growth
what are the 2 types of variation?
• continuous variation • discontinuous variation
describe continuous variation
two extremes and a full range of intermediates eg. height, weight, length of leaves
what causes continuous variation?
the interplay of genetics and environment
describe discontinuous variation
2 or more discrete categories with no intermediate values eg. eye colour, flower colour, blood group
what causes discontinuous variation?
alleles of a single gene or a small number of genes