Final answer:
Genetic variation is the diversity of genes in a population, while environmental variation refers to differences in traits due to environmental factors. Genotype-by-environment interaction occurs when genes and the environment interact to influence traits. Examples include coat colors in cats, changes in plant size due to environmental factors, and the influence of genetics and diet on body weight.
Step-by-step explanation:
Genetic variation refers to the diversity of genes within a population. It can result from mutations, genetic recombination during meiosis, and gene flow. An example of genetic variation is the different coat colors observed in a population of cats.
Environmental variation refers to differences in traits caused by variations in the environment. For instance, temperature, diet, and sunlight can affect the size and color of plants. Humans can also exhibit environmental variation, such as changes in skin color due to sun exposure.
Genotype-by-environment interaction occurs when the effect of an individual's genes on a trait is influenced by environmental factors. An example is the interaction between genetics and diet in determining body weight. Some people may be genetically predisposed to gaining more weight in a high-calorie environment.