Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Biol 243 Midterm > 2B > Flashcards

2B Flashcards

(49 cards)

Start Studying
1
Q

Brief overview of transcription

A
  1. Initiation
    2.Élongation
  2. Termination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is an organisms phenotype dependent on

A

-cell number
-cell type
-cell fxn

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Do cells have identical genome

A

Yes.. difference in expression (transcription)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Gene component

A

Promoter+transcriptional unit

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Promoter in gene?

A

DNA sequence (include TATA box)-> where transcription begins on chromosome

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where is promoter on gene???

A

Upstream/5’ of transcriptionalstart point of nontemplate/coding DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Transcriptional machinery role

A

Recognize and bind to promoter to initiate transcription

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Transcriptional machinery??

A

(RNA poly and transcription factors)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Transcriptional unit??

A

Part of gene copied into RNA (RNA coding region)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Where is the first ribonucleotide added in transcription

A

Transcription start site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where is last ribonucleotide added in transcription

A

Transcription termination site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

RNA poly use

A

-synthesize RNA transcript in 5’->3’ sense (add to 3’-OH.. read DNA template in 3->5)
-NO primer needed to initiate (can initiate from scratch)
-unwind and rewind DNA helix during RNA synthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

3 types of RNA poly

A
  1. RNA Pol I: rRNA
  2. RNA Pol II: mRNA
  3. RNA Pol III: tRNA
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

RNA pol I use

A

.rRNA-> transcription of noncoding gene (rRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

RNA Pol II

A

Transcription of coding RNA (mRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

RNA pol III

A

.tRNA… transcription of non coding RNA (tRNA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Step 1: transcriptional initiation

A

-mediated by DNA binding protein… specific regulatory sequence of gene (RDS)

2 types:
1. General transcription factor bind to promoter=> recruit RNA poly II in low basal level transcription
2. Transcriptional activator protein bind to enhancer region (far from promoter= DNA looping brings mediator and RNA poly to promoter=high level transcription)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Step 2: transcriptional elongation

A

-RNA poly moves along template DNA (3->5)
-DNA unwound in front of moving RNA poly and reannealing behind transcription Bubble
-ribonucleotide added to 3’ end of RNA transcript (synthesis in 5’->3’)
-growing RNA transcript displaced from DNA template allows reannealing back into dsDNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Step 3: transcriptional termination

A

-5’ sequence in DNA template=> termination after transcribed into RNA

  1. Rho-independent termination (rhohelicase)-> prokaryotes: terminator sequence in mRNA pairs with itself= G-C hairpin= RNA poly dissociate
  2. Rho-dependent termination (rho helicase)-> prokaryotes: terminator sequence in mRNA is recognized and bound by rhohelicase=> unwind RNA from template DNA and RNA poly
  3. Cleavage and polyadenylation specific factor (eukaryotes): poly-A-sequence in mRNA signals CPSF cleave completed mRNA transcript= separate fromRNA poly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

DNA molecule ds or as

21
Q

RNA molecule ds or ss

22
Q

WHERE does DNA replication occur

Study These Flashcards
A

Entire genome

23
Q

Where does transcription occur

Study These Flashcards
A

Select location in genome (aka gene)

24
Q

How many replications per cycle for DNA replication

Study These Flashcards
A

Replicate genome once/cell cycle

25
How many RNA synthesized. In transcription
Many RNA in many copies and copies vary through genome
26
DNA poly need or no need primer
Need cannot synthesize from scratch
27
RNA poly need primer or not
No, can synthesize de novo
28
DNA replication end product??
Daughter strand base paired wth parental template strand (semi conservative replication)
29
Transcription end products
RNA product is detached and ss (NOT remain base paired to template DNA)
30
Synthesis of new DNA in what direction
DNA replication in 5->3
31
Synthesis of RNA in what direction
5->3 (transcription)
32
Postranscriptional regulation of gene expression brief overview
Process mRNA for stability and proper translation 1.5’capping 2. 3’ polyadenylation 3. Splicing
33
Are the ends of prokaryotic and eukaryotic mRNA translated
NOO….5’ and 3’ are untranslated region -UTR regulate mRNA stability and translationalefficiency
34
What does 5’-UTR have
Ribosome binding site (RBS) -shine dalgarno sequence in prokaryotes -Kodak box sequence in eukaryotes… fxn in translationalinitiation
35
ORF
Open reading frame Region of mRNA translated and includes start and stop codons at borders
36
Going from DNA to polypeptide what is cut
DNA: promoter+ transcriptionalunit DNA->mRNA .mRNA: 5’UTR+ORF+ 3’UTR RNA->polypeptide Polypeptide: N-amino acid-C
37
Postranscriptionalmods of eukaryotic pre-mRNA
Pre-mRNA has processing in nucleus= mature translatable mRNA 1. 5’cap- moded Guanosine triphosphate added to5’end of mRNA and act as ribosomebinding site and protect mRNA from degradation 2. Poly (A) tail: string of adenine nucleotides added to 3’ end of mRNA by poly-A-polymerase(protect mRNA from degradation and increase translational efficiency 3.introns are removed/spliced during pre-mRNA processing= translatable mRNA
38
Posttranscriptional processing from pre-mRNA to mRNA
Pre-mRNA has coding segments and UTR (exon) and non coding segment (intron) Remove intron by splicing-> ORF (codon and UTR) .mRNA exported from nucleus intro cytoplasm (associate with ribosome)
39
.mMRNA splicing
Remove intron from pre-mRNA and joining exons=>mature mRNA Non coding segment (intron) spliced from pre-mRNA.=> UTR+ exons (codon) left in mature mRNA Splicing by spliceosome (made of 5 noncoding RNA (snRNA)… several proteins (snRNPs… small ribonucleoprotein) 1. Bind to intron-exon junction 2.loop intron out of pre-mRNA and bring exon closer 3. Clip intron at exon boundary 4.join exons
40
Alternative splicing
Generate diff proteins from 1 gene Splicing in diff combos= 2+ diff mRNA from gene= severalrelated protein products (isoforms) -diff isoforms made in diff tissues from same genes producing tissue specific genotype -increase # and variety of proteins encoded by genome
41
Posttranscriptional regulation by RNA interference
1. microRNA transcribed by RNA Pol II, siRNA (small interfering RNA) also transcribed 2. miRNA/siRNA precursor cleaved to ds RNA (substrate of RISC-RNA induced silencing complex) by dicer RNAse 3. RISC unwind 1 RNA strand which attracts binding of complementary mRNA 4. Binding of mRNA to RISC interferes with translation initiation/induces mRNA degradation (repress gene expression)
42
Transcriptional regulation
Control of mRNA synthesis Transcriptional rate depend on speed of transcriptionalinitiation (promoter strength)
43
Postranscriptional regulation
Process mRNA (affect stability and translational efficiency) Stability of mRNA depend on presence of 5’CAP and length of poly-A-tail
44
What does the expression level of a gene depend on
-abundance of mRNA -nucleotide sequence -translation
45
What does abundance of RNA depend on
-rate of synthesis (transcription) -degradation ofmRNA (Postranscription)
46
DNA transcriptionalregulation
-chromatin remodeling=> accessible for transcription -regulatory event at gene promoter and regulatory sequence
47
DNA postranscriptional regulation
-variation in pre-mRNA processing -removal of masking protein -variation in rate of mRNA breakdown -RNA interference
48
RNA translationalregulation
Variation in rate of initiation of protein synthesis
49
RNA post translationalregulation
-variation in rate of protein processing -removal of masking segments -variation in rate of protein breakdown

Biol 243 Midterm (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions