Many community ecologists are concerned about the effects of habitat fragmentation. In particular they worry that clear-cutting of old growth forests will produce small, isolated forest patches and that species will be lost from these smaller patches because small patches cannot support as long a food chain as bigger patches. This concern is based on which of the following hypotheses discussed in this chapter? a. The productivity hypothesis
b. The ecosystem-size hypothesis
c. The exploitation ecosystem hypothesis
d. HSS's the 'world is green' hypothesis

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.