test 3 prep

Question 1

what contributes to the high fidelity of DNA

Answer 1

DNA repair enzymes, base pairing rules, and proofreading capabilities of DNA polymerase III

Question 2

what does DNA polymerase require to start synthesizing a new strand?

Answer 2

free 3’ end. free template strand. dNTP. Mg++

Question 3

how can you tell if a baby belongs to a parent by using VNTR?

Answer 3

each VNTR fragment of the child must match one from the parents

Question 4

what is the relationship between the base sequence of coding strand and base sequence of mRNA?

Answer 4

they are the same, except the thymines are replaced with U’s in RNA

Question 5

determine size of mRNA- use what technique?

Answer 5

northern blotting

Question 6

identify a colony from a cDNA library using an antibody?

Answer 6

gene expression screening

Question 7

identify bacterial colonies who have taken up plasmids via transformation

Answer 7

antibiotic resistance analysis

Question 8

expression screening

Answer 8

detect protein of interest using antibodies. sticks to tubulin.

Question 9

Screening via hybridization:

Answer 9

use radioactive probe to identify specific sequences

Question 10

DNA moves towards (+/-) end

Answer 10

+ end. it’s negatively charged

Question 11

Southern Blotting

Answer 11

use hybridization to see which fragment in electrophoresis was of interest; identify DNA fragments complimentary to the probe

Question 12

what do you do if you want to find the size of RNA

Answer 12

northern blotting

Question 13

antibiotic resistance analysis is used for what process

Answer 13

identifying bacteria colonies that have taken up plasmids via transformation.

Question 14

in PCR, which end do primers face

Answer 14

3’

Question 15

steps of PCR

Answer 15

denature, anneal, repeat/extend

Question 16

Chain termination technique for DNA sequencing

Answer 16

a method of DNA sequencing based on the selective incorporation of chain-terminating dideoxynucleotides by DNA polymerase during DNA replication. stops chain, and then you can see where it stopped. how they mapped human genome

Question 17

what is the blue white test and what is it used for?

Answer 17

screens for plasmids with inserts (inserted DNA sequences)

Question 18

how would you produce DNA versions of mRNA sequences

Answer 18

cDNA synthesis

Question 19

discriminate between different allelic forms of B-globin?

Answer 19

RFLP

Question 20

in blue/white test- what exactly is turning blue? what gene is on/off?

Answer 20

lac Z gene . active lac z=blue, inactive (has plasmid) turns white

Question 21

relationship cAMP to CAP and what does it do

Answer 21

cAMP binds to CAP in absence of glucose, changing its conformation, so that CAP can bind to activator site

Question 22

which enzyme turns indicator dye blue?

Answer 22

B-galactoside

Question 23

how do you turn a tryptophan operon off?

Answer 23

Repressor protein floating around Inactive. When its inactive not bound to operator sequence- RNA polymerase can jump onto promter, transcribe, make mRNA. when tryptophan is present, it plugs into repressor, alters it shape so it can sit down. once its in, RNA can no longer sit there.

Question 24

tryp operon controlled by ___ protein

Answer 24

repressor

Question 25

tryp operon is (positive/negative) regulation

Answer 25

negative

Question 26

given template strand G A T C T G G T, what would be the positions of DNA products using dideoxy 'A' DNA?

Answer 26

cuts at : every T, as it forms a complementary A. fragment sizes: 3, 5, 8. 3 fragments.

Question 27

ascomycete

Answer 27

cup shaped indentations morel

Question 28

bread mold- type of fungus?

Answer 28

zygomycete

Question 29

spore print- type of fungus?

Answer 29

basidiomycte

Question 30

animal-like protists are organized how?

Answer 30

by mode of locomotion

Question 31

linear fungal growths

Answer 31

hyphae

Question 32

why is kelp a plant like protists

Answer 32

photosynthetic but no plant-like embryo

Question 33

leishmaniasis

Answer 33

flagellate pathogen

Question 34

silent mutation

Answer 34

base change that lets you stay with the same amino acid

Question 35

how could you produce 5' sticky ends? give a sequence and what it would turn into

Answer 35

GGATCC CCTAGG cut at first G (5') and last G: 5' G 3' CCTAG

Question 36

mendelson-stahl: F1, F2, and F2 if it had been conservative

Answer 36

F1: middle. a complete mix of parent strands both heavy and light leaves you in the middle F2: middle, light (semi conservative). half of parental strands are light, half are mixed F2 if conservative: light, heavy (middle makes one heavy one light)

Question 37

does every prokaryotic gene have to have an operator sequence? why or why not? give an example of one that doesnt

Answer 37

no. it only needs to have an operator if it has a repressor that needs to be turned on or off. an example of one that doesnt have an operator is one that's always on or always off! aka lac repressor structural gene

Question 38

when would you get a transversion as opposed to a missense, nonsense, etc?

Answer 38

when its an untranslated region recall that transverion is just a 1 letter switch; aka A to G

Question 39

is the genetic code universal? why or why not? explain

Answer 39

it's nearly unviersal- same 4 bases, 3 codon rule for living organisms, 64 options. however , human mitochondrial genes are an exception. also, bacteria use f-met instead of met as a starting codon.

Question 40

give a sequence for a restriction enzyme recognition site and then cut it to give it blunt ends

Answer 40

5' TTTAAA 3' AAATTT cut down the middle: blunt ends

Question 41

what do people with zeroderma pigmentosa form?

Answer 41

thymadine dimers

Question 42

in a bacteriophage- what requirements are needed for properly infecting e-coli?

Answer 42

phage arms + proper central segment

Question 43

size of genes of interest- hundreds or thousands of nucleotides?

Answer 43

hundreds

Question 44

how can viruses lead to cancer?

Answer 44

extra copies of oncogenes brought in by a virus virus could inserts itself into genome, disrupts normal reuglation screw up signlaing pathway that leads to division- cause abnormal division

Question 45

how can cell signaling pathways lead to cancer

Answer 45

disrupted pathway can lead to more divison- Many signaling pathways. Many multistep pathways. A mutation in any of these genes would screw up this process.

Question 46

what does p53 do?

Answer 46

calls in repair enzymes and signals apoptosis. if not fixed, damaged DNA is transcribed and replicated

Question 47

sequencing your DNA vs a regular cDNA library

Answer 47

1) The cDNA clone will only contain the sequences found in the mRNA, aka NO INTRONS DNA library = sequence of ENTIRE GENOME size: cDNA is only a few hundred nucleotides long. DNA library will be 10^5 nucleotides long

Question 48

what kind of disease is plague

Answer 48

bacterial. usually transmitted by insects or rats

Question 49

other exampls of bacterial illlnesses

Answer 49

STD's, legionnaires, tetanus, cholera, lyme

Question 50

transformed phenotype of cancer cells

Answer 50

de-differentiation alterd morphology angiogenesis chromosomal abnormalities metasteses

Question 51

draw a replication bubble with leading and lagging strands

Answer 51

3' on bottom, 5' on top. lag bottom left- points in to ORI. then lead bottom right, points out to fork. THEY PINT IN THE SAME WAY. top right: lag, point to ORI. top left: lead, point to fork.

Question 52

give some examples of transformed phenotype of cancer cells

Answer 52

increased angiogenesis altered morphology chromosomal abnormalities (anueploidy) immortality de-differentiation

Question 53

antibiotic resistance analysis

Answer 53

resistance genes are found on plasmids. if bacteria has a plasmid, resists ampicillin. if no plasmid, dies

Question 54

what do restriction enzymes do that is useful to us

Answer 54

produce genmoic DNA fragments for cloning or screening in a library

Question 55

what is expression screening

Answer 55

use antibodies to screen gene library

Question 56

determining size of mRNA

Answer 56

northern blotting