A nucleic acid is made of nucleotides, and nitrogenous bases are a part of a nucleotide.
DNA is a nucleic acid. The nucleotides in DNA are made up of a sugar (deoxyribose), a phosphate group, and one nitrogenous base (which will be either adenine, guanine, cytosine, or thymine).
Hope this helps!!
Answer:
The answer is b. Both of them are characterized by selective permeability.
Explanation:
- Option a. states that both, the nuclear and the cell membrane have two layers. This is only true for the nuclear membrane that consists of two lipid bilayers whereas the plasma membrane only contains one layer.
- c. Only the nuclear membrane has nuclear pores that connect the two bilayers. The pores act as protein channels or passages that allow transport of materials. The cell membrane does contain channel proteins or transmembrane proteins but not protein channels.
- d. The nuclear membrane separates nuclear contents from the cytoplasm whereas the cell membrane separates cellular contents from the extracellular environment.
Answer:
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). The order of these bases is what determines DNA's instructions, or genetic code.
Explanation:
