Which best explains what happens during crossing over? The chromosomes have electrical connections that allow them to line up randomly.
Paired chromosomes overlap and portions of DNA switch between chromosome.
Genetic material is switched because the chromosomes line up independently.
Chromosomes line up randomly and cross genetic information between unpaired chromosomes.

Chromosomes line up randomly and cross genetic information between unpaired chromosomes.

Explanation:

oxygen, selenium, tellurium, and polonium.

they're all from the same group as sulfur (group 16).

explanation:

two years ago, when picking flowers in the mountains back of yosemite valley, i found a book. it was blotted and storm-beaten; all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however; many of the inner pages were well preserved. and although all were more or less stained and torn, whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today; its granite pages have been torn and blurred by the same storms that wasted the castaway book.

two years ago, when picking flowers in the mountains back of yosemite valley; i found a book. it was blotted and storm-beaten, all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however, many of the inner pages were well preserved. and although all were more or less stained and torn; whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today, its granite pages have been torn and blurred by the same storms that wasted the castaway book.