Chapter 8, Problem 1R

Briefly describe the components of DNA, and explain its functional relationship to RNA and protein.

Summary Introduction

To review:

The components of DNA and its functional relationship to RNA and protein.

Introduction:

Deoxyribonucleic acid (DNA) is a molecule that carries the genetic information from one generation to the next. DNA is said to be the functional unit in all living organisms. The genetic information is stored as a code.

Explanation of Solution

Deoxyribonucleic acid is made up of four different deoxyribo nucleotides. They are deoxyadenosine triphosphate (dATP), deoxyguanosine triphosphate (dGTP), deoxycytosine triphosphate (dCTP), and deoxythymidine triphosphate (dTTP). Each deoxyribonucleotide is formed by the combination of four different nitrogenous base, deoxyribose and phosphates. They form the back bone of DNA with the phosphate group. The four chemical bases of DNA are adenine (A), guanine (G), cytosine (C), and thymine (T).

DNA is transcribed into mRNA (messenger RNA) and the mRNA sequence contains a number of codons. These codons are recognized by anti-codon region of t-RNA for the synthesis of proteins in the rough endoplasmic reticulum by adding amino acids. Later, the newly synthesized proteins undergo posttranslational modifications in order to become active functional proteins. Thus, the protein structure and their functions are decided by the DNA and RNA.

Conclusion

DNA is the hereditary material in almost all living organisms. In an organism, each cell has the same amount of DNA. Mostly DNA is located within the nucleus and it is called as the nuclear DNA. The small amount of DNA is present in mitochondria and it is called as the mitochondrial DNA.