Nucleotides Flashcards
Nucleic acids
Information carrying polymers from the monomer nucleotides
Nucleotide general structure
Molecules consisting of a negatively charged phosphate group bonded to a prentice sugar bonded to a nitrogenous base
What elements are in a nucleotide
Phosphor
Carbon
Hydrogen
Oxygen
Nitrogen
How are polynucleotides formed?
From the condensation of nucleotide monomers forming phosphodiester bonds between the phosphate group of one nucleotide and the Penrose sugar of the other
Bonds in a polynucleotide name
Phosphodiester bond
How are phosphodiester bonds formed?
The OH group in a phosphate group of one nucleotide and the OH group of a pentose sugar release H2O = condensation
Remaining oxygen bonds the 2 nucleotides
How is polynucleotides broken down?
In a hydrolysis reaction by adding H2O molecules which break the phosphodiester bonds
Examples of polynucleotides
Nucleic acids:
DNA
RNA
DNA structure description summary
2 nucleotides strands
Antiparallel to each other
Hydrogen bonds between complementary base pairs
Bases = A T C G
Double helix
Large molecule
DNA structure: 2 polynucleotide strands meaning
DNA contains 2 polynucleotide strands formed from condensation of nucleotide monomers with phosphodiester bonds between
DNA structure: anti parallel to each other meaning
The 2 polynucleotide strands run in opposite directions to each other
Where the 5’ carbon is at the top of one strand
Where the 5’ carbon is at the bottom of other strand
DNA structure: hydrogen bonding between strands
Between the nitrogenous bases are hydrogen bonds
DNA structure: complementary base pairs
So a purine base (A and G) always pairs and forms hydrogen bonds to a pyrimidine (T and G respectively)
What does Adenine form hydrogen bonds to and how many?
Thymine
= 2 hydrogen bonds
What does Cytosine form hydrogen bonds to and how many?
Guanine
= 3 hydrogen bonds