Nucleic Acids 3.8 Flashcards
Nucleotides
pentose monosaccharide, a phosphate and a nitrogenous base
Nucleic Acids
large polymers made from nucleotides which are the monomers
polynucleotide formation
phosphate group from 5th carbon of one nucleotide interacts with hydroxyl group from 3rd carbon of an adjacent nucleotide and a condensation reaction occurs forming water and phosphodiester bonds.
DNA
deoxyribose nucleic acid made up of 4 bases: adenine, cytosine, thymine and guanine
Pyramidines
the smallest bases, with single carbon ring structure.
thymine and cytosine
Purines
the larger bases, with double carbon ring structure.
adenine, guanine
Complementary Base Pairs
adenine and thymine
cytosine and guanine
will always be purine and pyrimidine
A+T
2 hydrogen bonds
C+G
3 hydrogen bonds
Double helix
DNA is a double helix which is 2 polynucleotide strands coiled together and joined by hydrogen bonds. The strands are antiparallel
RNA
ribonucleic acid helps DNA transfer info out of the cell.
DNA is too big so messenger RNA is sent out which is a single gene
RNA nucleotides
ribose sugar, phosphate and the base thymine is replaced by uracil which can still form two hydrogen bonds
DNA Extraction
- Grind sample to break down cell wall
- Mix detergent in to break down cell membrane
- Add salt to break hydrogen bonds between water and DNA
- Add protease enzyme to break down extra proteins associated to DNA
- Add ethanol on top to get DNA precipitate
- DNA should be white strands that you can spool with a glass rod