DNA molecules are formed from(a) organic bases(b) amino acids(c) deoxyribose(d) nucleotides

DNA molecules are formed from nucleotides. Here's a step-by-step explanation:

1. Nucleotides are the basic building blocks of DNA. Each nucleotide is composed of three parts: a phosphate group, a sugar molecule (deoxyribose in the case of DNA), and a nitrogenous base.

2. There are four types of nitrogenous bases in DNA: adenine (A), thymine (T), guanine (G), and cytosine (C). These bases are organic and are not amino acids.

3. The nucleotides are linked together to form a chain. The phosphate group of one nucleotide bonds with the sugar molecule of the next nucleotide, creating a sugar-phosphate backbone.

4. The nitrogenous bases stick out from this backbone and can bond with the bases of another chain, forming the famous double helix structure of DNA. The bases always pair in a specific way: A with T, and G with C.

So, while DNA does contain organic bases and deoxyribose, these are components of the nucleotides that DNA is actually made of. DNA does not contain amino acids; those are the building blocks of proteins.