How does the polymerase chain reaction relate to gel electrophoresis?

usually visualized (made visible) using gel electrophoresis. Gel electrophoresis is a technique in which fragments of DNA are pulled through a gel matrix by an electric current, and it separates DNA fragments according to size.

Explanation:

each of the 46 original chromosomes splits into two daughter chromosomes, so there are two sets of 46 daughter chromosomes that end up in each cell. human cells have 46 chromosomes. each chromosome consists of a pair of identical chromatids attached together by a structure called a centromere.

i think a) betsy can donate only blood to mark is correct because, mark and betsy have the same blood type. whereas nobody else has b+ blood so betsy can't donate to them.