John dalton described the atom with characteristics such as a. elements in a compound are always in a constant ratio b. in any element, all the atoms are the same c. atoms exist only on earth d. atoms are smaller than quarks e. all matter is made up of atoms

Ithink option a is correct because you cannot donate a different blood group than yours because it won't match.option a says betsy can donate to mark. they have the same blood group so donation can happen.

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.