two
A typical DNA molecule consists of two strands.
A DNA molecule typically consists of two strands.
They are arranged in nitrogenous mixters: A --- T C --- G
There are two types of hydrogen bonds found in a molecule of DNA: adenine-thymine and cytosine-guanine base pairs. These hydrogen bonds are responsible for the complementary pairing of the nitrogenous bases in DNA strands.
DNA is made up of many nucleotides. These are a sugar-phosphate backbone and nitrogenous bases. The two strands form a double helix (a spiral) with the nitrogenous bases in the middle, forming H-bonds with each other.
3
The DNA molecule has two strands connected by a sugar phosphate backbone.
The point of DNA is that it is a very long, continuous chain of nitrogenous bases (cytosine, guanine, adenine and thiamine linked by a C5 sugar (deoxyribose) and phosphate groups. There are 2 complementary chains that come together to create DNA (for every T base, there'll be a T complementary and vice versa and the same is true for C and G).
Four, out of whish 2 purines and two pyremidines
There are only 4 nitrogenous bases in DNA. These are adenine, thymine, guanine, and cytosine. Adenine will only pair with thymine, and guanine will only pair with cytosine.
HPV (human papillomavirus) has a double-stranded DNA genome, composed of one circular DNA molecule.
There is a set of 5 nitrogenous bases used in the construction of nucleic acids.