DNA Flashcards
Hershey & Chase
ID’ed the transorming factor as DNA
Griffith’s Experiment
Proved the presence of a transforming factor that is passed from generation to generation
Semi-Conservative
Each strand of DNA is used as a template or blueprint to synthesize a new strand.
Leading Strand
Where replication is continuous
Lagging Strand
Where replication is discontinuous.
Okazaki Fragment
Fragments of DNA that are generated b/c of discontinuous replication.
RNA Primer
Short strand of RNA that is synthesized by RNA primase needed for replication
Process of Replication
1.) signal is sent to start replication
2.) Direction of replication is 5’ —> 3’ direction
(DNA pol. II can only work in 5’ —> 3’ direction)
3.) Single stranded bind protein binds to unzip DNA
4.) RNA primase will synthesize RNA Primer
5.) DNA pol. III will begin to make the chain
6.) DNA pol. I will go in and remove the primer and replace them
with DNA sequence
7.) Fragments are glued by DNA ligase
8.) SSBP are removed
9.) 2 strands will re-zip
RESULT:
2 molecules of semi-conserved
Transcription
- Converts DNA into messanger RNA (mRNA)
- occurs in nucleus of cell
What is RNA?
- ribose nucleic acid
- sugar : ribose
- phosphate group
- nitrogen bases A=U
C=G (<–suppose to be 3 lines) - single stranded molecule
5 types of RNA
- ) mRNA
- ) tRNA
- ) rRNA
- ) snRNA
- ) siRNA
- All 5 found in urcratical cells
- 1-3 found in prokyratic cells
- 4&5 found in eurkyotic cells
Define mRNA
messanger RNA = encodes Amino Acid sequence formed during transcript
Define tRNA
- transfer RNA
- carry correct Amino Acid to ribosomes
- involved in translation
Define rRNA
- ribosomal RNA
- involved in formation of functional ribosome
- involved in translation
Define snRNA
- small nuclear RNA
- involved in transcription
