The aerobic threshold is the level of physical effort at which a person’s cells are just beginning to carry out fermentation to meet some of their energy needs. Marathon runners try to stay at or below the aerobic threshold so that they can go longer distances without experiencing difficulty. While running up and down the hills of San Francisco, the runner was focused on trying to maintain the pace he had when he was running on flat land. What impact did this focus have on his ability to maintain his aerobic threshold?

Duchenne muscular dystrophy is a serious condition caused by a recessive allele of a gene on the human x chromosome. the patients have muscles that weaken over time because they have absent or decreased dystrophin, a muscle protein. they rarely live past their twenties. how likely is it for a woman to have this condition? a) women can never have this condition.b) one-fourth of the daughters of an affected man would have this condition.c) one-half of the daughters of an affected father and a carrier mother could have this condition.d) only if a woman is xxx could she have this condition.