Only about 10 percent of the energy at one level of the food web is transferred to the next higher level. Most of the energy at each level is used by organisms to grow, create heat, and move. A diagram called an energy pyramid is used to display this transfer of energy. Why do you think using a pyramid shape is a good model to show how energy moves through an ecosystem?

Which of the following occurs most often in a population when genetic variation and overproduction are present? some organisms have a lower reproductive success than others. some organisms have a higher reproductive success than others. some organisms have no reproductive success. some organisms do not have genetic variation.

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.

Give two examples of what would occur if one of the pairs did not match or had an extra chromosomes. explain how this might occur, and if it would be dangerous to the individual. fast.