Which gas passes from the air sacs in the lungs into the blood capillaries? b. Where does this gas pass out of the bloodstream? What is it used for?

Explanation:

We breathe in oxygen from the external environment. Oxygen passes into our lungs and is passed into the blood capilaries.  Here it is carried to all the cells throughout the body.

It diffuses into the cells and is necessary for the final stages of energy production by aerobic respiration. Therefore, it is necessary for powering all cellular processes.

x would be the most and the least would be y because there are more fruit   and seeds than flock z has insects

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".