Variation Flashcards
What does the word variable mean in a genetic context?
Something which is variable is something that can come in different forms. For example, hair can come in a range of different colours, lengths, and textures, so we could say that hair colour is variable, hair length is variable, and hair texture is variable, because all three of these traits can have different forms.
What does the word population mean?
A population is all of the individual organisms of a particular species in a particular area. For example, if we think about human beings, we could count all of the people who live in a city like Auckland, and this would be the population of humans in Auckland.
What is genetic variation?
Genetic variation is the range of genotypes for a particular gene which are found in the population. If there are multiple genotypes for a particular gene found in the population, then the population has genetic variation.
What is phenotypic variation?
Phenotypic variation refers to the range of phenotypes for a particular trait that are found in the population. If there are multiple different phenotypes for a particular trait in the population, then the population has phenotypic variation.
Explain whether genetic variation in a population always results in phenotypic variation.
Genetic variation does not always result in phenotypic variation. For example, imagine a population of ten organisms, five with the genotype AA and five with the genotype Aa, where A gives black fur and a gives white. There is genetic variation in the population, because the individuals do not all have the same genotype. However, all of the individuals have black fur, so there is no phenotypic variation.
