Variations Flashcards
(11 cards)
Zoom into genes from a cell
Cell, nucleus, DNA, chromosome, gene
What is inherited variation
Difference between organisms passed to offspring by their parents in reproduction
What is environmental variation
Differences between organisms caused by environmental factors
Environmental factors
Things in an environment that can change an organism
Continuous variation meaning
Where individuals have values within a range, with no clear categories, such as height, and it is controlled by both genes and environment
Discontinuous variation meaning
Where individuals fall into a number of distinct classes, such as eye colour, and mainly controlled by genes
What is an allele and an example
A different version of a gene such as the gene being eye colour, with one allele being brown and the other being blue
How many alleles in one gene and what are they called
2, one from your mother (maternal) and one from your father (paternal)
How do genes decide which allele to take into appearance
Some alleles are dominant so if they are present you will have that feature. Others are recessive so if a dominant allele is present, it won’t be shown.
How is it possible for someone to have blonde hair when their family has brown
Their parents could have dominant brown hair genes, but with a recessive allele of blonde hair (Bb) Only 50% of DNA is taken from the sperm and egg so she may have gotten the recessive blonde alleles from both her parents, resulting in her having blonde hair
What graph/ table is used to show the alleles
Punnett Square
