Phenotypes can be directly observed. Phenotypes are the outward appearance of an organism that express the genotype. An example of a phenotype is hair color, or eye color.
Answer:
The Agouti gene controls the distribution of black pigment. The dominant allele A restricts black pigment to the points of the horse (mane, tail, lower legs and ear rims), as seen, for example, in bays and buckskins.
Age- younger people have smaller capacity
gender-males have larger capacity
muscle mass
aerobic fitness
diseases of the respitorary system