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Mirco Test 3 Picking
Micro 2123 Test 3 OSU Picking
84
Microbiology
Undergraduate 2
10/28/2010

Additional Microbiology Flashcards

 


 

Cards

Term
Why is DNA more stable than RNA
Definition
OH Group
Term
DNA Makeup
Definition
Adenine, Guanine, Cytosine, Thymine
Term
RNA Makeup
Definition
Adenine, Guanine, Cytosine, Uracil
Term
Backbone in DNA
Definition
DeoxyRibose - Sugars and phosphate joined by ester bonds
Term
Backbone in RNA
Definition
Alternating Phosphate and Ribose
Term
Purines
Definition
Adenine and Guanine
Term
Pyrimidine
Definition
Cytosine and Uracil
Term
Nucleic Acid polarity
Definition
5' to 3'
3' to 5'
Term
Base Pairing
Definition
A-T (U) and G-C
Term
Supercoiling
Definition
Allows to DNA to be "packed" into cell.
Topoisomerases create and relive supercoils as well as regulate them.
Term
Replication
Definition
Copies information from one strand to a new, complementary strand.
Term
oriC
Definition
Point where replication begins. Replication moves from a 5' to 3'.
Term
DNA Helicase
Definition
Melts and unwinds strands of DNA. Also recruits Primase.
Term
Primase
Definition
Begins replication. RNA primer forms 3'Oh for DNA to attach. There is one per okazaki fragment.
Term
DNA Polymerase III
Definition
Is recruited to each strand. Polymerase Synthesizes 5' to 3' on each strand. Main replication polymerase.
Term
RNase H
Definition
Removes primers.
Term
DNA Polymerase I
Definition
Fill gap in DNA strand.
Term
DNA ligase
Definition
Seals nicks in strands.
Term
Where do new bases always occur
Definition
3' -OH
Term
Where does energy for base addition come from.
Definition
Phosphate groups of the new nucleotide triphosphate being added to the strand.
Term
Leading vs Lagging Strand
Definition
Leading strand is continuous. Lagging strand is discontinues, and will be or is composed of okazaki fragments.
Term
Plasmids
Definition
Extrachromosomal pieces of DNA. Advantages = Specilized tasks like metoblism of rare food sources, Antibiotic-resistance genes, resistance to toxic materials, ect.
Term
High copy vs Low copy number plasmids
Definition
Low copy number - one or two copies per cell, segregate similarly to chromosomes. High Copy Number plasmids - Up to fifty copies per cell, divide continuously, randomly segregate to daughter cells.
Term
Transcription (General)
Definition
Creates complementary RNA structure. Has three steps initiation, elongation, and termination.
Term
Transcription Initiation
Definition
Initiation - Bind polymerizing machine, first monomer to template - DNA polymerase, RNA polymerase, Ribosomes.
Term
Transcription Elongation
Definition
Elongation - Core polymerase adds RNA to 3' end. Added bases are always complementary.
Term
Transcription Termination
Definition
Termination - Pause at stem loop structure bound by RHO protein causes row dependent termination. Stem loop followed by UUUU sequence causes termination.
Term
RNA Polymerase I
Definition
Large molecular machine; has 4 protein subunits + sigma factor which binds to DNA and reads sequence.
Term
Sigma factor (RNA Poly) * Check
Definition
Smaller proteins (more than 1 type) that guides RNA poly I to site on DNA; dictates where the RNA binds. RNA polymerase binds promoter 10 and 35 bases pair upstream of start site where poly starts the unwinding and sigma factor is released.
Term
Start Codon
Definition
AUG (Methionine)- Always starts protein synthesis.
Term
Stop Codon
Definition
Term
RBS codon
Definition
Term
tRNA
Definition
Very stable. Carriers amino acid to new protein made in ribosome.
Term
rRNA
Definition
Enzyme for protein synthesis (RNA and Enzyme) - Ribosomal RNA.
Term
Anticodon loop
Definition
base pairs found on tRNA that correspond to the mRNA.
Term
aminoacyl-stem
Definition
Stem on tRNA loop where amino acid can bind.
Term
rRNA A site
Definition
Where incoming tRNA carrying an amino acid binds on the ribosome
Term
mRNA P Site
Definition
where the tRNA that has the growing protein is bound on the ribosome
Term
mRNA E Site
Definition
where the empty tRNA that is about to be ejected is bound on the ribosome.
Term
Monocistronic mRNA versus polycistronic mRNA
Definition
Wether or not a mRNA has more than one binding site for protein creation.
Term
Horizontal transfer
Definition
Transfer of large genetic material from cell to cell without being spawn.
Term
Transformation
Definition
Up take of "naked" DNA from enviroment
Term
Conjugation
Definition
Bacterial "sex". Pillus is appendage used for transfer. F plasmid is code that enables cell to have/use pillus. F+ is the male giving cell, and F- is female receiving cell which will form and F plasmid.
Term
HFR
Definition
High frequency recombination - F Factor integrates on bacterial chromosome and tries to transfer entire chromosome.
Term
Transduction
Definition
Viruses inject DNA, then bacteriaphage can transfer DNA to another cell from host.
Term
Restriction endonuclease
Definition
Protection against foreign DNA. Cuts DNA that enters cell unless it has been methylated at specific cut sites.
Term
Vertical Transfer
Definition
Transfer of material through ancestry.
Term
Point mutations
Definition
Change a single base pair. http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/M/Mutations.html#silent

 

 

Term
Silent mutation (point)
Definition
No affect on cell but affect on genotype.
Term
Missense Mutation
Definition
Variable affect on the cell.
CGA -> CAA
Term
Nonsense mutation
Definition
Changes a codon to stop. total affect dependent upon how close to the end of the strand the mutation occurs.
Term
Frameshit mutation
Definition
insert or deletes a single base which alters all of the downstream codons. usually results in drastic changes.
Term
Ames Test
Definition
Test using salmonella and the bacterias ability to make histidine. Used to identify compounds that are mutagens based on the compounds ability to cause reversion.
Term
Exision repair
Definition
type of repair used to repair crosslinked thymidine dimers. Low risk,cut out the sequence with DNA poly 1 based on the other stands sequence.
Term
SOS Repair
Definition
High risk. uses RecA, induced when there is so much damage to the cell that it is unlikely to survive. Last Ditch effort. Error prone. May mean replacement with other parts of chromosomes.
Term
Transposable elements (transponsons)
Definition
Transposons are jumping genes that move around the genome causing mutations.
Term
How do bacterial cells sense the environment.
Definition
Two component signal transduction. Sensor kinase protein binds to signal, hunts food, uses chemical cues. Cytoplasmic response regulator takes phosphate from sensor and binds to the chromosome to alter transcription rates of genes.
Term
Regulating transcription
Definition
Sigma factor guides RNA polymerase to initiate transcription at promoter. Activator binds DNA sites to next promoter and increase frequency of that genes transcription. Repressor binds to DNA site on top of promoter and lowers frequency of that genes transcription.
Term
LacOperon
Definition
Enables utilization of lactose as a food source, Beta-galactosidase breaks down lactose into glucose and galactose.
Term
LacOperon promoter binds using
Definition
Sigma factor binding.
Term
Lac Operon operator
Definition
DNA sequence where lactose repressor LacL binds. Overlaps with promoter.
Term
Lac Operon Inducer
Definition
Lactose or allolactose - Binds to repressor to cause it to fall of the operator.
Term
Catabolite repression
Definition
Glucose effect on cAMP levels - high glucose means low cAMP, low glucose means high cAMP.
Term
Replication Steps
Definition
1st - Unwind DNA with helicase
2nd - primer is made from primase
3rd - DNA poly III starts making DNA
4th - Get rid of primer with RNase
5th - Fill in nics with DNA poly (?????)
Term
Virus vs viroid versus prion
Definition
Virus has small genome (DNA or RNA) encapsulated in a protein. Viroid is RNA only usually plant pathogen. Prion is misfolded protein.
Term
Filamentous capsid
Definition
Long tube of protein with genome in side. Tube is made up of hundreds of identical protein subunits.
Term
Icosahedral capsids
Definition
20 triangular sides, with each triangle being made up of at least 3 identical capsid proteins.
Term
Complex capsids
Definition
Mixture of icosahedral and filamentous shapes. Many bacteriaphages have this form.
Term
Envelopes
Definition
Membrane that surrounds capsid produced by host cell. Only produced by hosts who do not have cell wall.
Term
SS+ RNA Virus
Definition
Can be translated directly by host ribosomes. One of first proteins translated will be replicase or RNA-dependant RNA polymerase
Term
SS- RNA virus
Definition
(must carry their own replicase enzyme) can’t be translated by ribosome so it must carry its replicase with it (must make a + strand for protein translation and to serve as a template for make – strand genomes
Term
DS RNA virus
Definition
one of the strands can be translated directly, but it usually carries its replicase with it
Term
Retrovirus
Definition
+ Strand single strand RNA + reverse transcription into DNA
Term
SS DNA Virus
Definition
Parvoviruses. Carries its on Polymerase.
Term
DS DNA virus
Definition
Pox viruses
Term
Typical Virus Life Cycle
Definition
1. Attach to host cell
2. Get viral genome into host cell
3. Replicate genome
4. make viral proteins
5. assemble capsids
6. Release progeny viruses from host cell
Term
Bacteriophage life cycles (Lytic)
Definition
Kills host, follows same typical virus cycle.
Term
Lysogenic
Definition
integrates into host chromosome until SOS response is initiated – then it begins the lytic cycle
Term
Example of a + ss RNA lytic virus life cycle
Definition
Polio virus, makes poly protein
Term
Example of a ds DNA lysogenic life cycle
Definition
Lamda Phage
Term
Example of retrovirus lifecycle
Definition
buds off (enveloped) so makes for a long slow disease process that (for HIV) affects immune system cells
Term
Stages of virus growth when culturing them
Definition
1. Eclipse - after entry/uncoating, no noticeable viruses
2. Rise - Begin to see viruses
3. Burst - the number of viruses released per host cell upon lysis of the host cell
Term
Budding
Definition
How animal enveloped animal viruses gain their envelope
Term
Plaque
Definition
a whole in a lawn of bacteria caused by their lysis by phages
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