Term
What is the structure of a nucleic acid?
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Definition
| sugar back bone+base+phosphate |
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Term
How is DNA joined?
What bonding connects it?
What structure does it form? |
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Definition
DNA is joined at 5' and 3' carbonds.
The strands are anti parrallell and connected by hydrogen bonding.
It forms a helical structure. |
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Term
| What are the 5 nitrogenous bases? What two catagories are they split up into? |
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Definition
Adenine ,Guanine and Inosine=Purines
Cytosine Thymine and Uracil=Pyramidine |
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Term
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Definition
H bons are weak comparitivly therefor DNA can seperate easily.
Strands can be melted by heating and sepeperate.
The strands once cooled can return back together.
*It takes more thermal energy to break a G-C bond then to break an A-T bond. |
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Term
When is DNA is replicated what occurs?
What end are new bases added to?
How does DNA grow? |
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Definition
When DNA is replicated a nucleotide triphosphate is added.
The energy from the two phosphates is used to attach the nucleotide.
New bases are added to the 3' end but DNA grows from 5' to 3'. |
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Term
| What is semiconservative Replication? |
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Definition
It describes a method of how DNA is replicated. DNA replication would produce 2 copies that each contained one of the original and one of the new strands.
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Term
| What are the Proteins DNA Pol 3, DNA clamp, Primase and RNA primers do? |
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Definition
All are part of transcription.
DNA Pol 3=Adds nucleotides and has a proofreading job.
DNA Clamp= holds DNA Poly 3 in place.
-it is a subunit of of Poly 3
-it can increase the rate of synthesis by 1000x
Primase=adds RNA so Pol3 can bind
-RNA poly
-RNA primers are 10 to 12 nucleotides.
RNase=Removes RNA |
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Term
| What do the proteins DNA Poly 1, Ligase, Gyrase and Helicase do? |
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Definition
-DNA Poly 1=fills the gap from the RNase and removal of RNA primers.
Ligase= closes the nicks
Gyrase=unwinds DNA from helocase
Helicase=opens the two strands. |
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Term
| What is the central dogma of theory? |
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Definition
It was created by Frank Crick.
DNA----> RNA= Transcription
RNA----> to Protein=Translation
DNA being transcribed in the same amino acid language as RNA.
RNA is being transated to proteins by the ribosomes. Proteins and amino acids are like different languages. |
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Term
| Differences between DNA and RNA? |
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Definition
-In DNA 2'H deoxyribose is used.
It is double stranded and uses Thymine.
-RNA uses ribose as its back bone sugar and is single stranded. It also uses Uracil. |
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Term
| What are the three types of RNA and what do they do? |
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Definition
mRNA=messenger RNA carries a message from the DNA to protein.
rRNA=ribosomal RNA and its part of the ribosome(translation)
tRNA=transfer RNA and it transfers amino acids(translation) |
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Term
Is DNA or RNA more unstable? Why
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Definition
RNA is more unstable:
1)Single Stranded-weaker structure
2)OH group- less stable
RNases- degrade RNA |
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Term
| What are the steps of Initiation(Transcription) |
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Definition
1)sigma factor binds to RNA polymerase.
2)sigma factor binds to promoter
3)RNA polymerase unwinds the DNA and begins to Transcribe. |
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Term
What are the steps of Elongation?(transcription)
What are the steps of RHO-dependent termination? |
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Definition
-RNA polymerase moves from the 5' to 3' end of DNA making a complimentary DNA strand
-RHO-dependent:
1)transcription pauses as RNA polymerase reaches the hairpin loop
2)RHO binds to the RNA and dissociates the polymerase. |
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Term
| What is RHO-independent termination? |
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Definition
1)RNA polymerase reaches a hairpin.
2)It puases at a region of adenine's.
3)The RNA polymerase dissociates from the DNA. |
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Term
What do the codons:
AUG
UAA
UAG
UGA
mean? |
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Definition
AUG=Met
UAA=stop
UAG=stop
UGA=stop |
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Term
How is RNA bonded as far as tRNA?
What is an acceptor stem(3')?
What is an anticodon? |
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Definition
-RNA is covalently bound to an amino acid.
Acceptor stem(3')=where the RNA accepts the amino acid
Anti codon loop= base pairs to the codon
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Term
| What is the structure of ribosomes? |
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Definition
-consists of over 50 proteins and rRNA.
-The rRNA has catalyctic activity(ribozyme)
-Consists of two subunit:30s and 50s |
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Term
What is the:___on the Ribosome?
A site?
P site?
E site?
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Definition
Asite= where ribosome enters
Psite=Where amino acid is joined.
Esite=Where amino acid exits |
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Term
| What are the components of Tranlsation? |
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Definition
-mRNA
-Ribosomes
-Factors that associate with the ribosomes:
1)initiation factors
2)Elongation factors
3)Release factors |
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Term
What are the steps of inititaion(translation)
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Definition
1)IF3 brins the 30s ribosome to mRNA.
2)the 30S subunit binds to the Shrine Delargno Sequence.
3)IF1 blocks the A site of the ribosome.
4)IF2 brings mehionine to the P site
5)The 50s binds to the 30s and release IF1 and IF2. |
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Term
| What do the three Initiation factors do? |
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Definition
IF1=blocks the a site
IF2= brings the amino acid to the P site of the ribosome
IF3= brings mRNA and the 30s subunit together |
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Term
| What are the steps of Elongation? |
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Definition
1)EE-TU binds a tRNA and moves it to A.
2)Peptidyltransferase creates a bond between the two amino acids.
3)EF-G moves the 50s subunit forward.
4)The 30s subunit follows it forward and tRNA exits. |
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Term
| What are the Elongation factors? |
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Definition
EF-TU=moves tRNA to site A
EF-G+moves the 50s subunit forward |
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Term
| What are the steps of termination(translation)? |
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Definition
1)RF1and RF2 binds to the A site
2)Peptidyltransferases release tRNA.
3)RF3 enters, removing RF1and RF2.
4)RRF adn EF-G break apart subunits
5)IF3 binds to the 30s subunit. |
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Term
| What are the termination factors?(translation) |
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Definition
RF1 or RF2=bind to the A site and activate peptidyl -transferases
RRF=binds to EFG and hydrolyzes GTP to separate the two ribosomal subunits. |
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