Which conclusion about the meaning of y is correct if the allele combination yy is for yellow seeds? yellow and dominant green and recessive yellow and recessive green and dominant

You can conclude that the meaning of the Y is yellow and dominant is the allele combination Yy is for yellow seeds. Yy means that the phenotype shown will reflect the capital letter, or the dominant one, which turns out to be yellow.

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.