Question

Compare and contrast RNA and DNA

Answer 1

Answer:

Both the Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA) are vital for the existence of life on Earth as they are responsible for the storage and reading of genetic information. Both are linear polymers composed of bases, sugars and phosphates. Although nearly identical, there are still some differences in their structure and function.

1. Function

DNA is responsible for the replication and storage of genetic information. It contains and provides a blueprint for the organism

RNA is responsible for conveying the information stored in DNA to specialized structures called ribosomes,  that will produce functional products such as proteins.

2. Structure

a) DNA is built of two strands that form a double helix whereas RNA is contains only one strand. Both are made of nucleotides composed of a 5-carbon sugar molecule and a nitrogenous base.

b) DNA is much longer with millions of base pairs compared with the few thousands in RNA. DNA also forms chromosomes, which are an effective packaging way for the extensive genetic information.

c) DNA is composed of a sugar known as deoxyribose whereas RNA contains ribose sugar. The later lacks the hydroxyl modifications found in the former.

d) Both DNA and RNA share the bases  Adenine (‘A’), Guanine (‘G’) and Cytosine (‘C’) . However, DNA contains the base Thymine (‘T’), whereas RNA contains Uracil (‘U’). These bases pair as: DNA A-T, C-G and RNA A-U, C-G.

e) Deoxyribose sugar is more stable than ribose sugar due to the absence of one oxygen-containing hydroxyl group. RNA is also more susceptible to enzyme attacks due to its large helical grooves.

f) DNA is more vulnerable to UV light damage, whereas RNA is more resistant.

3. Location

DNA is found in the nucleus and in to a less extent in the mitochondria. RNA however is formed in the nucleolus and then moves to specialized regions in the cytoplasm. Where depends on the type of RNA formed.