How DNA is double stranded while RNA single stranded???
Answers
Explanation:
Deoxyribonucleic acid (DNA) and Ribonucleic acid (RNA) are perhaps the most important molecules in cell biology, responsible for the storage and reading of genetic information that underpins all life. They are both linear polymers, consisting of sugars, phosphates and bases, but there are some key differences which separate the two1. These distinctions enable the two molecules to work together and fulfil their essential roles. Here, we look at 5 key differences between DNA and RNA. Before we delve into the differences, we take a look at these two nucleic acids side-by-side.
DNA vs. RNA – A Comparison Chart
Comparison
DNA
RNA
Full Name
Deoxyribonucleic Acid
Ribonucleic Acid
Function
DNA replicates and stores genetic information. It is a blueprint for all genetic information contained within an organism
RNA converts the genetic information contained within DNA to a format used to build proteins, and then moves it to ribosomal protein factories.
Structure
DNA consists of two strands, arranged in a double helix. These strands are made up of subunits called nucleotides. Each nucleotide contains a phosphate, a 5-carbon sugar molecule and a nitrogenous base.
RNA only has one strand, but like DNA, is made up of nucleotides. RNA strands are shorter than DNA strands. RNA sometimes forms a secondary double helix structure, but only intermittently.
Length
DNA is a much longer polymer than RNA. A chromosome, for example, is a single, long DNA molecule, which would be several centimetres in length when unravelled.
RNA molecules are variable in length, but much shorter than long DNA polymers. A large RNA molecule might only be a few thousand base pairs long.
Sugar
The sugar in DNA is deoxyribose, which contains one less hydroxyl group than RNA’s ribose.
RNA contains ribose sugar molecules, without the hydroxyl modifications of deoxyribose.
Bases
The bases in DNA are Adenine (‘A’), Thymine (‘T’), Guanine (‘G’) and Cytosine (‘C’).
RNA shares Adenine (‘A’), Guanine (‘G’) and Cytosine (‘C’) with DNA, but contains Uracil (‘U’) rather than Thymine.
Base Pairs
Adenine and Thymine pair (A-T)
Cytosine and Guanine pair (C-G)
Adenine and Uracil pair (A-U)
Cytosine and Guanine pair (C-G)
Location
DNA is found in the nucleus, with a small amount of DNA also present in mitochondria.