Answer:
DNA structure DNA is made up of molecules called nucleotides. Each nucleotide contains a phosphate group, a sugar group and a nitrogen base. The four types of nitrogen bases are adenine (A), thymine (T), guanine (G) and cytosine (C).
Explanation:
Answer:
I want to say it is the middle layer. But not 100% sure. Sorry if its wrong.
Answer:
Sun.
Explanation:
The Sun and other gasses work together and increase the greenhouse gasses.