Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BIOL 203 > Lecture 2 - 3 (Ch 7) > Flashcards

Lecture 2 - 3 (Ch 7) Flashcards

1
Q

The 5 types of RNA and their function are ___

A
  1. mRNA will be translated to proteins at the ribosome 2. rRNA forms part of the ribosome 3. tRNA carries AA to ribosomes 4. retrovirus RNA uses reverse transcriptase to produce complementary DNA 5. micro-RNA regulate gene expression in plants and animals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

DNA coding strand and mRNA transcript have the ___ polarity

A

same

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

Transcription/gene expression is regulated in 3 different ways; these are ___

A

promotor, termination sequence, and exon/introns

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

Promotors help to regulate the transcription by ___; it is ___ to the process and is the ___

A

initiating transcription; essential; the most common method of regulating gene expression

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

Termination Sequence helps to regulate the transcription by ___; it is (same/different) according to eukaryote, prokaryote, and individual genes

A

signaling the end of transcription; different

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

Exons and introns are found in ___; the coding information is found in ___, while ___ is removed

A

eukaryotes; exon; intron (Eukaryotes have Exons)

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

In bacteria, 1 transcript leads to ___ protein; this RNA transcript (can/can’t) be translated straightaway because ___

A

multiple protein; can; The RNA transcript is mRNA because there is no need to process it. It also does not have a nucleus that has a separate mechanism of translation.

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

In eukarya, 1 transcript leads to ___ protein; this RNA transcript (can/can’t) be translated straightaway because ___

A

1 protein; can’t; the RNA transcript is called pre-mRNA because it has introns, which must be excised.

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

Describe the relationship between the promotor region, the 5’ untranslated region, coding region, termination region, 3’ UTR and the transcribed region in coding sequence of the bacteria. How will it look different within eukaryotes?

A

5’ –[Promotor] { [5’ UTR][Coding][3’ UTR] } [Termination]–3’ Promotor signals beginning of transcribed region; Transcribed region contains 5’ UTR, coding seq, and 3’ UTR; Termination signals end of transcription, and is not transcribed; In eukaryotes, there will be intermittent exons and introns between 5’ and 3’ UTR

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

Upstream of gene refers to ___; downstream of gene refers to ___

A

the area of the template DNA before start of mRNA transcription; the area after the end of mRNA transcription; upstream 5’—->3’ downstream —————————————————- downstream 3’ upstream

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

Translation ___; it takes place at the ___

A

converts genetic message carried by mRNA into sequence of AA joined together by covalent peptide bond; ribosome

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

The result of translation is ___

A

Polypeptide

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

The relationship between polypeptide and protein is ___

A

polypeptide folds to make up all or part of a protein (i.e. folded polypeptide from gene 1 + folded polypeptide from gene 2 = protein)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Why is polpeptide called a POLYPEPTIDE?

A

peptide indicate 2 - 5 AA; polypeptide indicate many more AA

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

The start codon is ___, and (is/isn’t translated)

A

AUG; is translated to Met

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

The bond between AA is ___

A

covalent peptide bond

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

DNA is antiparallel but isn’t ___

A

a palindrome

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

In most genome, a given region of DNA can be transcribed and then translated into protein in (one/both) directions; the notable exception is

A

one; restriction enzyme sites

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

Restriction enzymes are also called restriction endonucleases because ___

A

the enzyme goes into the DNA at the MAJOR groove, read it, and then cut it at the palindromic sequence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Translation begins when mRNA ___

A

attaches to the ribosome in a manner that places the start codon (AUG) in the correct position

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

DNA, RNA, and polypeptides add in 5’->3’ direction because ___

A

they all use the same rnx.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Peptide Bond: Compare the P-site and the A-site of the ribosome

A

P-site: peptide already added; A-site: next AA will be brought in

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Peptide Bond: At the A-site during elongation, what factors are present before and after peptide bond is formed? What are released/changed?

A

Before, AA-tRNA-EFtu*-GTP complex is at the A-site (EFtu is Elongation Factor) After, AA-tRNA EFtu is released and recycled; GTP is hydrolyzed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Peptide Bond: When tRNA is at both P and A-site, peptide bond is formed by ___ at ___;

A

peptidyl transferase; large ribosomal subunit

25
Q

Peptide Bond: The two steps of peptidyl transferase are ___

A

at the P-site, fMET and tRNA bond is broken; at the A-site peptide bond between fMET and next AA is formed, causing elongation of the AA

26
Q

Peptide Bond: Peptidyl transferase is a ___, called ____.

A

catalytic RNA molecule called ribozyme

27
Q

Translocation: After peptidyl transferase activity, the P-site contains ___; the A-site contains ___

A

uncharged tRNA (w/o AA); tRNA bound to fMET-AA

28
Q

Translocation: The next step is translocation of the ____ to the ___ sites, which is initiated by ___

A

uncharged tRNA at P-site and tRNA bound to fMET-AA at A-site, to E-and P-site respectively; EFtu and GTP hydrolyzing

29
Q

Translocation: The integrity of condon frame during translocation is ensured by the ___ ; this unit is rejected when ___

A

EF-GDP unit; when the tRNA bound to fMET-AA is bound correctly to the P-site

30
Q

The sites of large ribosomal subunit are ___

A

E-P-A

31
Q

tRNA reads mRNA in a ___ direction; it has an ____ sequence

A

5’->3’; tRNA has anticodon (3’->5’) sequence

32
Q

Codons have 3rd nucleotide “wobble”/redundancy because ____

A

the 3rd nucleotides are often silent mutations; even with the mutation, the expression of the gene (AA sequence) is conserved

33
Q

What are the 3 stop codons?

A

UGA, UAG, UAA

34
Q

Locate AUG, UGA, UAG, and UAA within this model of the coding DNA: 5’ –[Promotor] { [5’ UTR][Coding][3’ UTR] } [Termination]–3’

A

5’ –[Promotor] { [5’ UTR][*Coding][^3’ UTR] } [Termination]–3’ *AUG is translated! ^UGA/UAG/UAA is NOT translated.

35
Q

DNA replication mechanism and DNA as molecule of heredity is ___ across life forms

A

conserved

36
Q

Life-forms differ from one another due to ___

A

differing quantity and sequence of DNA

37
Q

Relate evolution, natural selection, and mutation:

A

Evolution is a theory that all organisms are related by a common ancestor that have diversified over time via natural selection acting on spontaneously occuring mutation

38
Q

Phenotypic variation and allele variation are related because ___

A

Phenotypic variation indicate allele variation

39
Q

DNA Polymerase uses (dNMP/dNTP), which contain ___

A

dNTP, which contain deoxyribose, nitrogenous base, and tri-phosphate group

40
Q

In DNA replication, __ is released

A

PPi (2 phosphate groups)

41
Q

Why must the DNA be a helix?

A

If the diameter of 3.4 A is constant, but the bond length between bases vary (A-T v. C-G), DNA must be a helix

42
Q

3 attributes of DNA replication shared by all organisms are:

A
  1. Each strand of parental DNA molecule remains INTACT during replication, 2. Each parental strand serves as a template for ANTIPARALLEL and COMPLEMENTARY daughter strand, 3. Results in formation of two identical daughter duplexes with 1 PARENTAL + 1 DAUGHTER STRAND (semiconservative)
43
Q

How was the semiconservative replication of DNA empirically discovered? What trait of N was exploited? What was the assay?

A

Meselson and Stahl; 15N is heavier than 14N, which is naturally occurring; 1. Gen 0: 15N medium so all DNA had 15 N; following Gen in 14 N medium; 2. DNA samples from each generation spun to form a gradient by weight 3. DNA analysis by weight

44
Q

Meselson and Stahl: Describe the bands for t0 Describe how each alternative models of DNA replication (conservative, semiconservative, dispersive) were proven/disproven.

A

at t0, all heavy at first cycle, conservative was ruled out because all bands indicated hybrid (15N-14N) DNA. If conservative, then there will be 1:1 ratio of heavy to light. at second cycle, dispersive was ruled out because there was 1:1 light to hybrid band. If dispersive, then all bands will remain hybrid.

45
Q

To figure out number of origin of replication in plasmids, what property of T was exploited? What was the assay?

A

Radioactive T (T*) emits weak light; At various time points, take e- micrograph.

46
Q

What about the e- micrograph picture indicated that there was 1 ori in plasmids?

A

there was always a bubble where DNA seemed to come apart that was indicated by T*

47
Q

In unidirectional replication model, the ori will be ___. In bidirectional replication model, the ori will be ___

A

right adjascent to the termination site vs. away from the termination site

48
Q

In eukaryotes, multiple “bubbles” were visible with T* e- microscopy. That suggests ___

A

multiple ori

49
Q

According to different cell types in Eukaryotes, ori fire at ___

A

different priorities according to gene expression

50
Q

Replisomes are ___; they assemble at the ___

A

CONSERVED enzymes and proteins involved in DNA replication; replication fork

51
Q

7 parts of the replisome are ___

A
  1. Helicase that binds to the origin and unwind dsDNA
  2. SSB that binds to ssDNA and keeps it ss
  3. Primase that syntheizes RNA primer
  4. DNA Polymerase that adds dNTP to 3’ end of RNA primer & the DNA strand
  5. Sliding Clamp that anchors DNA Polymerase to DNA for high processivity
  6. 5’-3’ exonuclease and polymerase degrades RNA primer and replaces rNTP to dNTP
  7. Ligase makes ss gap between Okazaki fragments and between adjascent lagging/leading strand fragments with P-d bond
52
Q

Problem during replication specific to the bacteria is ___; to compensate, the bacteria uses ____ to

A

supercoiling while unwinding the circular DNA helix; topoisomerase to cut, rotate to unwind, and then rejoin DNA

53
Q

Steps to processing RNA primer in lagging strand (mention when nucleoside triphosphate and nucleoide is used):

A
  1. DNA Pol I binds to ss gap between DNA and RNA primer and replaces RNA with DNA by using nucleoside tri-phosphate
  2. DNA Ligase replaes pol I at DNA-RNA ss gap and binds them together with p-d bond
54
Q

DNA Ligase works only in lagging strands to anneal Okazaki fragments. T/F?

A

F. Gap btw lagging and leading at ori also important

55
Q

DNA proofreading occurs with ___’s ____ activity; 3 steps to the process are___

A

DNA polymerase 3’-5’ exonuclease activity;

  1. DNA plymerase makes an error
  2. Exonuclease removal of mismatched base pair
  3. Daughter strand resumes DNA synthesis
56
Q

Consensus sequence’s function is to _____; they are conserved in their ___ (state why); the bases themselves are ___

A

serve as recognition sequences for protein binding in replication (but promoter itself is the binding site); presence upstream of the promotor (b/c essential for replication initiatino), and spacing (b/c provides physical space for proteins to bind to DNA template); similar but variable

57
Q

In yeast, multiple replication origins are called ___ and have ___ DNA sequence

A

Antunomously Replicating Sequences (ARS); conserved

58
Q

In bacteria, comparison of single replication origin found consensus sequences called ___ and ___

A

13-mer (TATA box) and 9-mer

59
Q

In eukaryotes besides yeast, replication origins have ____ DNA sequence; this means that DNA is “marked” for replication via ___, rather than ___

A

non-conserved; chromatin modification, rather than consensus sequence

BIOL 203 (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions