Nucleic Acids Flashcards
What is composition of a nucleotide?
Made up of a 5-carbon sugar, nitrogenous base and a phosphate group
What are the 4 nucleotides in RNA?
Cytosine, uracil, guanine, and adenine
What are the 4 nucleotides in DNA?
What does it lack that makes it different from RNA?
Cytosine, thymine, guanine and adenine
- DNA lacks the hydroxyl group at carbon-2 (making it deoxyribose)
Describe the polymerization of nucleotides (DNA Formation)
- Polymerize via phosphodiester linkages
- 3’ hydroxyl group of polymer forming a covalent bond with the 5’ phosphate group of the incoming nucleotide
RNA/DNA molecule always starts with _____ and ends with _______
Starts with 5’ phosphate group and ends with 3’ hydroxyl
Polymerization occurs in what direction?
5’ to 3’
What is more stable; G-C or A-T? Why?
G-C is more stable because it form 3 hydrogen bonds (A-T only forms 2)
DNA is made of _________ held together by _______
DNA is made of two antiparallel strands held together by hydrogen bonds between the bases
What is the backbone of DNA made of?
It is a sugar-phosphate backbone held together by bases on the inside
Two grooves in DNA- what are they and why do they matter?
- There is a major groove where the strands are far apart and minor where they are closer together.
- Major groove allows more DNA binding proteins. This affects transcription
What is more stable- DNA or RNA?
Which came first?
DNA is more stable than RNA
RNA came first in evolution
What is special about RNA’s function?
RNA is able to fold into complicated 3D structures like proteins. It can then work like an enzyme catalyzing certain reactions
