Me , describe how bonds contain energy and what the energy is used for

Chemical bonds contain potential energy.

Explanation:

Chemical bonds always contain potential energy. The atoms of the bond want to move to a lower energy to become more stable.. The energy for breaking bonds only comes when stronger bonds are formed.  This energy is used to tear apart the bonds holding the Hydrogen atoms together. The strength of the covalent bonds depend on the overlap between the valence orbitals of the bonded Atom.

the major parts of the digestive system:

salivary glands.

pharynx.

esophagus.

stomach.

small intestine.

large intestine.

rectum.

accessory digestive organs: liver, gallbladder, pancreas.