Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

Microbio 3220 > Exam 3 - Lecture 16 > Flashcards

Exam 3 - Lecture 16 Flashcards

1
Q

archaea are like bacteria in _________/_____________

A

looks/architecture

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

archaea are similar to eukaryotes in the __________ that replicates and expresses archaeal genomes

A

machinery

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

what three things does DNA polymerase require?

A
  • template
  • primer
  • dNTPs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

are eukaryotic chromosomes linear, circular, or both?

A

linear

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

eukaryotic chromosomes are wound around _________

A

histones

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

how many origins of replication do eukaryotes have?

A

multiple

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

how many DNA polymerases are responsible for eukaryotic DNA replication? what are they?

A

3
- polymerase alpha-primase
- polymerase epsilon
- polymerase delta

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

what is the role of polymerase alpha-primase?

A

lays down a RNA/DNA hybrid starting point

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

what is the role of polymerase epsilon?

A

synthesizes the leading strand

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

what is the role of polymerase delta?

A

synthesizes the lagging strand

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

what are three problems presented by linear DNA molecules?

A
  • chromosome end may be digested by DNases
  • DNA ends can fuse with other DNA molecules
  • the “end replication problem” of linear DNA replication
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what are telomeres? what base are these regions rich in?

A
  • repetitive DNA sequences at the ends of chromosomes
  • rich in guanosine bases (called the “G-tail”)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are telomerases and their functions?

A
  • ribonucleoprotein complex enzyme that forms telomeres and maintains them
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

telomerase has an _________ _____ ___________ that partially matches the G-tail sequence

A

internal RNA template

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

what is the starting point for telomerase DNA synthesis?

A

the 3’-OH of the G-tail

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

what activity of telomerase allows for the increase of the length of the G-tail?

A

reverse transcriptase activity

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

what shape are archaeal chromosomes?

A

circular

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

true or false: some archaea have histones associated with their chromosomes.

A

true!

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

do most archaea have a single or multiple origins of replication?

A

most only have one origin of replication

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

archaeal replisome proteins are similar to:

A

eukaryotic ones

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

how many RNA polymerases do bacteria have?

22
Q

eukaryotic transcription occurs in the _________ and RNA transcripts must be moved to the __________

A

nucleus; cytoplasm

23
Q

true or false: eukaryotic genes are spliced.

24
Q

true or false: eukaryotic transcription and translation are coupled.

25
how many major eukaryotic RNA polymerases are there?
three: RNA pol I, II, & III
26
what is the role of RNA polymerase I?
catalyzing rRNA synthesis
27
what is the role of RNA polymerase II?
catalyzing mRNA synthesis
28
what is the role of RNA polymerase III?
synthesizes tRNA molecules
29
what elements make up the core promoter in eukaryotic transcription?
- TATA box - BRE (TFIIB recognition element) - Inr (initiator element) - DPE (downstream promoter element)
30
what is the difference between the eukaryotic and archaeal promoters?
- archaea don't have a DPE - their BRE and TATA boxes are at different base pair locations
31
how many sigma factors do archaea and eukaryotes have?
they don't have any
32
what do eukaryotes and archaea use instead of sigma factors?
transcription factors (TFs)
33
what are the modifications made to initial transcripts before they are ready to be translated?
- 5' cap of 7-methylguanosine added - removal of introns/splicing together exons - addition of 3' poly-A tail
34
introns are removed by a large complex of proteins and RNA molecules unique to eukaryotes called the:
spliceosome
35
what are the two fates of lariats (spliced introns)?
- degradation - processing into ncRNA
36
a single eukaryotic gene can code for different final proteins due to:
alternative splicing
37
how many domains in alternative splicing found?
just one: eukaryotes (the others don't really get spliced at all, so)
38
approximately how long is the 3' poly-A tail?
200 nucleotides long
39
what are three similarities that archaea have with eukaryotic transcription?
- RNA pol resembles RNA pol II - archaeal promoters and binding of RNA pol - no sigma factors
40
what are four similarities that archaea have with bacterial transcription?
- transcription occurs in cytoplasm - coupling of transcription/translation - mRNA is polycistronic - introns are rare
41
which requires more initiation factors: eukaryotic or bacterial translation?
eukaryotic translation
42
when the initiator tRNA interacts with the 40S subunit in eukaryotic translation, what subunit is formed?
43S subunit
43
when is the 60S subunit recruited to the 43S subunit?
when the 43S subunit finds a start codon on the activated (bridged) mRNA
44
what is a polysome? what domain of life can it be obsevred in?
- polysome: more than one ribosome translating the same mRNA molecule - observed in eukaryotes
45
what is the first codon in archaeal translation?
methionine
46
true or false: archaea do not have polycistronic transcripts.
false, they certainly do
47
true or false: archaeal transcription and translation are coupled.
true
48
what are the three levels at which regulation of cellular processes can take place in all three domains of life?
- transcriptional - translational - posttranslational
49
what are two transcription activator binding sites? do they act near or far from the promoter of the gene being regulated?
- upstream activator sequences (UASs); act near the promoter - enhancers; act from a distance
50
what are transcription repressor sites called? do they act near or far from the promoter of the gene being regulated?
silencers; act from a distance
51
match the following: 1. acetylation of histones 2. methylation of histones a. represses transcription b. promotes transcription
1b 2a
52
name the six levels of eukaryotic gene regulation.
- transcription initiation - splicing efficiency - mRNA trafficking - mRNA stability/degradation - translational rate - post-translational modification

Microbio 3220 (24 decks)

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