7. What holds combinations of atoms together in molecules?
O protons and electrons
atomic magnetism
nuclear forces
chemical bonds

Chemical bonds.

Chemical bonds hold the atoms of a molecule together thereby forming covalent bonds, when two atoms share electrons.

image result for describe the various types of gene mutationsghr.nlm.nih.gov

the types of mutations include: missense mutation: this type of mutation is a change in one dna base pair that results in the substitution of one amino acid for another in the protein made by a gene. nonsense mutation: a nonsense mutation is also a change in one dna base pair.

explanation:

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