Where are the bases, sugars, and phosphates in DNA structure?

Answer 1

I will write the answers for you in points so that you can benefit from it Inshallah...

*The DNA molecule (deoxyribonucleic acid) takes the shape of a double helix (anti-parallel strands), this shape has been determined correctly by Watson and Crick in 1953...

* the monomer of DNA molecule is called a nucleotide.

* the nucleotide consists of a nucleoside and a phosphate group.

* The nucleoside consists of a nitrogenous group and a deoxyribose sugar (ribose in the case of RNA)..

*The nitogeneous bases (heterocyclic) can be divided into two categories: purines (two rings) and pyrimidines (one ring)...

*Purines are either Adenine (A) or Guanine(G), wherease pyrimidines are Thymine (T) and Cytosine (C), [ in RNA Thymine is replaced by Uracil U]..

*Those nitogeneous bases are connected by hydrogen bondings; two hydrogen bonds between A&T, and three H-bonds between C&G (complementary base paring)..

*The phosphate group is connected to the C'3 or C'5 of the deoxyribose sugar by a " 3',5' phosphodiester bonds".

*the C'1 of the deoxyribose sugar has a Beta linkage with the C1 of pyrimidines, or C9 of purines...

*The adjacent nitogeneous bases in one strand interact by hydrophobic forces and van der waals interactions ( a thing that might some times cause a dimer- a damage in DNA that needs repair-)..

*DNA molecule makes one complete turn every 10 residues, and the distance between the strands is 20 A...

*The DNA is circular in bacteria cells mitocondrion, chloroplast... DNA is linear in chromosomal genome,,, and DNA can be either circular or linear in viruses..

Answer 2

If you imagine the DNA double helix molecule to be like a twisted rope ladder, the rungs of the ladder are the paired bases, and the ropes going up the side are chains of sugar and phosphate.

Answer 3

Adenine, thymine, cytosine, and guanine. A pairs with T and C with G.

Answer 4

They are on the two nucleotides.