Biochemistry of Nucleic Acids Flashcards
What is the Central Dogma?
Formation of DNA into a protein form
DNA>RNA>Protein
What are Nucleotides?
-Base, Sugar and Phosphate
What are Nucleosides?
- Base and Sugar
- NO Phosphate
How would you determine type of sugar?
-The R group attached to 2’ end of the nucleotide
What R group is attached to a Nucleotide?
-Single hydrogen bond
What R Group is attached to a Nucleoside?
-Hydroxyl (OH)
Name base pairs for DNA
Adenine and Thymine (AT)
Guanine and Cytosine (GC)
Name base pairs for RNA
Adenine and Uracil (AU)
Guanine and Cytosine (GC)
Name the two Nitrogen bases that hold DNA molecule together through Hydrogen Bonds
Purines
Pyrimidines
What is Nomenclature?
The naming of something
What are DNA and RNA Building blocks?
-Help formation of DNA/RNA
Where are end are DNA Nucleotides added to?
Free ‘3’ Ends
What is a free hydroxyl group?
-When OH R group of a nucleotide is left exposed
What is a Phosphodiester bond?
When two HIGH ENERGY bonds are formed between 3’ end and 5’ end of nucleotides joined.
What direction do DNA Strands run in?
-Parallel and Antiparallel
What does the Leading Strand do?
- Replicates Inwards
- 3’ end open
What does the Lagging Strand do?
- Replicates Outwards
- Replicated in ‘Ozaki’ fragments
- Primers required to start off each fragment
What enzyme joins Ozaki Fragments?
Ligase-enzyme
What enzyme matches complementary DNA nucleotides?
DNA Polymerase
What enzyme unzips the DNA double helix to from a replication fork?
Helicase- breaks hydrogen bonds
What are Anti-Retro Viruses and how do they work?
- Fight off Retro-Viruses such as HIV
- Joins to 3’ end of a nucleotide and incorporates into DNA
- Higher affinity to 3’ end than Retrovirus
- Inhibits enzyme ‘Reverse Transcriptase’ stops –Retrovirus replicating
Why is DNA Replicated before cell division?
-Ensure daughter cells have full set of DNA from genome
What does it mean by DNA Replication is ‘Semi-Conservative?’
X1 Old and X1 New strand
What are DNA Primers on lagging strand for?
- Cannot add to 5’ end, and primers allow for be added to 3’ end
- Removed at end of DNA Replication
- Primase-enzyme synthesises Primers- made of RNA
