A fellow student asks, "How is it possible that six feet of DNA
can fit inside a single, microscopic nucleus of a cell?" If you
were to unravel a ball of yarn,
it would probably be able to circle
around your house (that's a
long distance!). Use this
comparison to answer
your fellow student's question.

DNA is wrapped around proteins known as histones to form chromatin. Packing the DNA into nucleosomes condenses the DNA approximately sevenfold. It can be further organized by winding the chromatin into more compact structures. Coiling the chromatin around itself decreases the space it occupies by another sixfold or so. Through a series of similar compacting strategies, the entire genome can fit inside the nucleus of a single cell.

Explanation:

•there must be variation for the particular trait within a population.

•the variation must be inheritable (that is, it must be capable of being passed on from the parents to their offspring).

•individuals with one version of the trait must produce more offspring than those with a different version of the trait.good

explanation:

the answer is c.) there is a warm front in region a and a stationary front in region b.