exam 3 (chapter 17, 18) Flashcards Preview

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Flashcards in exam 3 (chapter 17, 18) Deck (74)
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1
Q

DNA>RNA (nucleotide>nucleotide)

A

Transcription

2
Q

RNA>protein (nucleotide>amino acid)

A

Translation

3
Q

The process by which we turn DNA into phenotypes (what we physically look like)

A

Gene Expression

4
Q

The one DNA molecule transcribed into RNA

A

Template Strand

5
Q

Pries two strands of DNA apart and joins together RNA nucleotides complementary to the DNA template

  • Assembles RNA nucleotides in the 5’>3’ direction
  • Does not need a primer
A

RNA Polymerase

6
Q

DNA sequence where RNA polymerase attaches

  • Indicates which DNA strand is to be copied
  • Not transcribed
A

Promoter

7
Q

DNA sequence that signals the end of transcription, is transcribed

A

Termination

8
Q
  • Only the area of one gene (or a few genes) is copied
  • Highly selective
  • **Only the genes currently needed are copied
  • No primer needed
A

Transcription

9
Q

The entire DNA molecule is copied, always essentially the same, requires a primer

A

DNA Replication

10
Q

Produces mRNA, transcription and translation take place simultaneously

A

Prokaryotic Transcription

11
Q

Produce pre-mRNA, it is extensively modified to become mRNA before leaving the nucleus

A

Eukaryotic Transcription

12
Q

mRNA removed before translation

A

Introns

13
Q

Remaining mRNA to be used during translation

A

Exons

14
Q

The process of removing introns in the nucleus

A

RNA Splicing

15
Q

Consists of snRNP subunits; binds to pre-mRNA at multiple sites along the intron, snip the intron, and join the exons

A

Spliceosomes

16
Q

Small nuclear ribonucleoproteins; composed of snRNA and proteins, recognize introns

A

snRNPs

17
Q

A ribozyme, a catalyst that is a RNA molecule, not an enzyme (protein)

A

snRNA

18
Q

Messenger RNA; carries the codon from the DNA to the ribosome

A

mRNA

19
Q

Transfer RNA; brings amino acids to the ribosomes

A

tRNA

20
Q

Ribosomal RNA; component of ribosome, most abundant RNA

A

rRNA

21
Q

Structural components of spliceosomes when removing introns from eukaryotic pre-mRNA

A

sRNA

22
Q

The messenger RNA nucleotide triplets

A

Codon

23
Q

Consists of rRNA and proteins organized into 2 subunits

A

Ribosome

24
Q

Contains a mRNA binding site

A

Small Subunit

25
Q

Lines up the tRNA

A

Large Subunit

26
Q

Holds the tRNA carrying the growing polypeptide chain

A

P-site (peptide tRNA)

27
Q

Holds the tRNA carrying the next amino acid

A

A-site (aminoacyl tRNA)

28
Q

Discharges tRNA

A

E-site (exit site)

29
Q

Change in a single nucleotide (1 letter changed)

example: sickle cell disease

A

Point Mutation

30
Q

Point mutation in the third base pair of a codon that does not change the amino acid

A

Silent Point Mutation

31
Q

Point mutation that does change the amino acid

A

Missense Point Mutation

32
Q

Point mutation that replaces an amino acid with a stop codon

A

Nonsense Point Mutation

33
Q

Additions of one or more nucleotides in a gene

A

Insertions

34
Q

Deleting of one or more nucleotides in a gene

A

Deletions

35
Q

Errors during replication

**1 nucleotid in 10,000,000,000

A

Spontaneous Mutations

36
Q

Physical or chemical agents that cause mutations

A

Mutagen

37
Q

What are 3 examples of mutagens?

A

X-rays, UV light, carcinogens

38
Q

Insertions or deletions of 1 or 2 nucleotides in a shift in the reading frame

A

Frameshift Mutations

39
Q

The switch on the DNA that allows transcription to occur

A

Operator

40
Q

The operator, promotor, and the gene to be transcribed (entire set of DNA necessary)

A

Operon

41
Q

Binds to the operator and blocks the attachment of RNA polymerase to the promotor

A

Repressor

42
Q

Codes for repressors; can have their own promotor, located outside the operon, must be activated by a corepressor

A

Regulatory Gene

43
Q

Transcription is usually on, but can be inhibited; repressor normally unbound, corepressor needed in order for repressor to bind to the operator

A

Repressible Operon

44
Q

Transcription is usually turned off, but can be stimulated; repressor normally bound to the operator, induced required to inactivate the repressor so transcription can occur

A

Inducible Operon

45
Q

Synthesis repressed by a chemical signal (product of repressible operons; generally function in anabolic pathways, which synthesize essential end products from raw materials (dehydration synthesis)

A

Repressible Enzymes

46
Q

Synthesis induced by a chemical signal (product of inducible operons), generally function in catabolic pathways which break down nutrients into simpler molecules (hydrolysis)

A

Inducible Enzymes

47
Q

All cells contain the same DNA but what is expressed varies by cell type

A

Differential Gene Expression

48
Q

Regulation occurs during

a) Chromatin modification
b) Transcription
c) RNA processing
d) mRNA degradation
e) Initiation of Translation
f) Protein processing

A

Stages of Gene Expression

49
Q

Adding acetyl groups

A

Acetylation

50
Q

Removing acetyl groups

A

Deacetylation

51
Q

Without acetyl groups, the histones attach to each other and transcription is ??

A

prohibited

52
Q

With acetyl groups, the DNA is exposed, allowing ??

A

Transcription

53
Q

Chromatin includes DNA and proteins
-Proteins called histones
Histones have tails that can be modified

A

Chromatin Modification

54
Q

Inheritance of traits not directly involving the DNA

A

Epigenetic Inheritance

55
Q

A regulatory protein that binds to DNA and affects the transcription of specific genes

A

Transcription Factors

56
Q

Control elements close to the promoter

A

Proximal Control Elements

57
Q

Control elements distant from the promotor (1000s of nucleotides away)

A

Distal Control Elements

58
Q

Transcription factors
**RNA polymerase requires the assistance of transcription factors to initiate transcription (some transcription factors are required in all protein-coding genes)
Transcription initiation complex includes RNA polymerase and transcription factors
DNA segment bends to put activators close to the promoter
**Done via DNA bending proteins
**When in contact, forms the transcription initiation complex

A

Transcription Factors

59
Q

A segment of eukaryotic DNA containing multiple control elements, usually located far from the gene whose transcription it regulates

A

Enhancer

60
Q

A protein that binds to DNA and stimulates gene transcription

A

Activator

61
Q

How does coordinated transcription occur in eukaryotes?

A

They have similar control elements, such as hormones

62
Q
  • Prevent attachment of ribosomes
  • Initiation of translation can be suspended for all mRNA at the same time
  • In eggs, until fertilization
  • In seeds
  • In plants, during periods of darkness
A

Initiation of Translation

63
Q

Proteins have to undergo chemical modification to activate them, lifespan of proteins regulated

A

Protein Processing

64
Q

A protein that binds to other proteins to mark them for degradation

A

Ubiquitin

65
Q

Eukaryotes– DNA far from the gene

A

Enhancer

66
Q

Where does transcription occur?

A

Nucleus

67
Q

Where does translation occur?

A

Ribosomes

68
Q

An enzyme that joins each amino acid to the appropriate tRNA

A

Aminoacyl-tRNA Synthetase

69
Q

A codon at one end of a tRNA molecule that base-pairs with a particular complementary codon on an mRNA molecule

A

Anticodon

70
Q

Signals the start of translation, AUG

A

Start Codon

71
Q

Signals translation to stop; UAG, UAA, UGA

A

Stop Codon

72
Q

Proteins have to undergo chemical modification to activate them

A

Protein Processing

73
Q

Bacterial mRNA typically degraded with ??

A

a few minutes

74
Q

Eukaryotic mRNA survives for

A

hours, days, or weeks