Yes they did. It is generally known that amphibians breathe through their skin.
Answer:
A nucleotide consists of a sugar molecule (either ribose in RNA or deoxyribose in DNA) attached to a phosphate group and a nitrogen-containing base. The bases used in DNA are adenine (A), cytosine (C), guanine (G), and thymine (T).
Explanation:
Dependent on both the mineral assemblage of the protolith and the temperature and pressure of formation...
Or
both minteral content of the prolith and the temperature and pressure formation..
I really don't know my answer wrong or right....if it's wrong pls forgive me....