What are the bonds found between amino acids in a polypeptide chain

Amino acids are joined by peptide bonds in a polypeptide chain. A peptide bond is one in which the molecules of a carboxyl react with the amino group of another molecule. A molecule of water is then formed and release, leaving the functinal groups to bond together and form a polypeptide chain.

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.

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