Answer:phenotype
Explanation:
Phenotype is a physical appearance or biochemical characteristics which is influenced both by its genotypes and the environment. In other words,its a particular trait that is expressed, e.g. height,color,behaviour etc.
In the above mentioned case,Thomas inherited his parents's genotype(atheletic),but it was not expressed because of his adoptive parents' disinterest in sports.
Answer: Genetic variation describes naturally occurring genetic differences among individuals of the same species. Gene duplication, mutation, or other processes can produce new genes and alleles and increase genetic variation. New genetic variation can be created within generations in a population, so a population with rapid reproduction rates will probably have high genetic variation. And there are the reasons.
The answer is B.The respiratory system supplies the oxygen that the cardiovascular system transports to the different cells for the production of energy.
