What is the difference between adenine thymine guanine and cytosine

At the most basic level, DNA is wrapped around proteins known as histones to form structures called nucleosomes. The DNA is wrapped tightly around the histone core. This nucleosome is linked to the next one by a short strand of DNA that is free of histones.

This fiber is further coiled into a thicker and more compact structure. At the metaphase stage of mitosis, when the chromosomes are lined up in the center of the cell, the chromosomes are at their most compacted. They are approximately nm in width, and are found in association with scaffold proteins. In interphase, the phase of the cell cycle between mitoses at which the chromosomes are decondensed, eukaryotic chromosomes have two distinct regions that can be distinguished by staining.

There is a tightly packaged region that stains darkly, and a less dense region. The darkly staining regions usually contain genes that are not active, and are found in the regions of the centromere and telomeres. The lightly staining regions usually contain genes that are active, with DNA packaged around nucleosomes but not further compacted.

Concept in Action. Watch this animation of DNA packaging. The DNA molecule is a polymer of nucleotides. Each nucleotide is composed of a nitrogenous base, a five-carbon sugar deoxyribose , and a phosphate group. There are four nitrogenous bases in DNA, two purines adenine and guanine and two pyrimidines cytosine and thymine. A DNA molecule is composed of two strands. Each strand is composed of nucleotides bonded together covalently between the phosphate group of one and the deoxyribose sugar of the next.

From this backbone extend the bases. The bases of one strand bond to the bases of the second strand with hydrogen bonds. Adenine always bonds with thymine, and cytosine always bonds with guanine. The bonding causes the two strands to spiral around each other in a shape called a double helix. Ribonucleic acid RNA is a second nucleic acid found in cells.

What is the difference between Adenine and Guanine. Adenine is one of the two purines found in nucleic acids. The functional group present in adenine is an amine group. In DNA, the pyrimidine base, thymine forms a complementary base pair with adenine. In RNA, uracil, which is also a pyrimidine base, forms a complementary base pair with adenine. Usually, adenine forms two hydrogen bonds with its complementary nucleotide , either thymine or uracil.

The complementary base pairing occurs via hydrogen bonding between the two nitrogenous bases, assisting the stability of the nucleic acid structure. Adenine is shown in figure 1. Adenine is synthesized in the liver. It is derived from inosine monophosphate IMP. The synthesis of adenine requires folic acid. Adenosine triphosphate ATP is the mostly occurring chemical energy sources, which energizes the cellular processes.

ATP contains two high energy phosphates. The cofactors, nicotinamide adenine dinucleotide NAD and flavin adenine dinucleotide FAD along with ATP are involved in the cellular respiration as carriers of energy from one reaction to the other. Guanine is the other purine, which occurs in nucleic acids. Two functional groups are present in Guanine : an amine group on C-2 and a carbonyl group on C Three hydrogen bonds are formed between guanine and cytosine.

If it's a really big gene, it may be 10, base pairs, or essentially 10 kilobases long. Lawrence C. Brody, Ph. Featured Content. Introduction to Genomics.