What is the structure of DNA?
DNA stands for deoxyribonucleic acid and is the basic unit of the genetic material that is housed in the nucleus of eukaryotic cells.
DNA was first visualised by Watson and Crick, who described it as having a 'double-helix' structure.DNA is made up of nucletoides - nucleotides are the basic component of DNA. Nucleotides are composed of a phosphate ion, deoxyribose pentose sugar and a nitrogenous base.Genetic information is expressed in DNA and it forms chromosomes. which are two strands of DNA that lie anti-parallel to one another.There are 4 deoxyribonucleotides: A, T, C and G and they combine in specific ways. A = T and G = C. This is known as the base pairing rule. The bases form hydrogen bonds between the bases and keeps the strands together. Nucleotides are chemically joined to form a strand, and these bonds are called phosphodiester bonds.
Related Biology A Level answers
All answers ▸Describe the sequence of events of the clotting cascade that will lead to a blood clot in a damaged blood vessel
What is the action of Insulin in glucose regulation?
The herbicide atrazine works by disabling plastoquinone, one of the proton pumps in photosystem II. Explain how atrazine would kill a susceptible plant (5 marks) (OCR A specimen paper 3)
How does synaptic transmission across a neuromuscular junction work?