what is DNA write its structure and function
Answers
Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the development and function of living things. All known cellular life and some viruses contain DNA. The main role of DNA in the cell is the long-term storage of information. Deoxyribonucleic acid or DNA is a molecule that contains the instructions an organism needs to develop, live and reproduce. These instructions are found inside every cell, and are passed down from parents to their children.
DNA structureDNA 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. Human DNA has around 3 billion bases, and more than 99 percent of those bases are the same in all people, according to the U.S. National Library of Medicine (NLM).
Answer:
- DNA stands for Deoxyribonucleic Acid.
- It is made up of two helices wound around each other.
- Its main function is the transmission of genetic information along generations.
Explanation:
- A DNA helix is comprised of:
- Two negatively charged phosphate backbones.
- A deoxyribose sugar is attached to each of the phosphate groups by a phosphodiester bond.
- A nitrogenous base, like a purine (adenine, guanine) or a pyrimidine (cytosine, thiamine), is attached to the deoxyribose sugar by a glycosidic bond.
- The two helices of the DNA are attached to each other by hydrogen bonds between the nitrogenous bases (adenine base pairs with thymine with two hydrogen bonds, guanine base pairs with cytosine with three hydrogen bonds).
- The negatively charged DNA is stabilised by positively charged histone proteins which also helps in DNA compaction.
- The major function of the DNA is to act as a genetic material. The characteristics of the parent are transmitted to the offspring through the DNA.