Brainscape's Knowledge GenomeTM

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


See full index

MCAT Biochem > RNA and the genetic code > Flashcards

RNA and the genetic code Flashcards

1
Q

This type of RNA is translated into polypeptides after it reaches the ribosome

A

mRNA (Messenger RNA)

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

This type of RNA has anticodons that pair with the codons, and allows the RNA to bind the correct AA for the sequence

A

tRNA (transfer RNA)

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

This type of RNA helps to catalyze peptide bond formation and form the ribosomes

A

rRNA

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

What is the wobble base and why can it lead to silent mutations?

A

The last (third) base in a codon. Since many codons can code for the same AA, a change in the wobble base doesn’t usually lead to a change in AA sequence.

The wobble base is the best part of the codon to mutate, since it usually doesn’t end up changing the AA sequence

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

This mutation occurs when 1 AA substitutes for another

A

Missense

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

This mutation occurs when a stop codon is inserted early

A

Nonsense

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

This mutation occurs when a base is inserted or deleted, and causes the AA sequence to shift (the most catastrophic mutation)

A

Frameshift

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

This mutation most often occurs due to a mutation of the wobble base and doesn’t actually change the AA sequence

A

Silent

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

Silent, missense and nonsense mutations are referred to as ____ mutations since only one base is being changed

A

Point

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

What three things are added to hnRNA to make it into mRNA?

A

Exons have to be spliced and glued back together, a cap is added to the 5’ end to act as ribosome binding site, and a tail is added to the 3’ to help stop degradation of important genetic info when the RNA enters the cytoplasm

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

This is the name for the DNA strand that’s used as the template for transcription

A

Anti-sense

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

This is the name for the DNA stand that is complimentary to the DNA strand being transcribed, and is ultimately the same as the new RNA strand being created

A

Sense

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

This type of RNA polymerase is found in the nucleolus and synthesizes rRNA

A

RNA polymerase I

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

This type of RNA polymerase is found in the nucleus and synthezies hnRNA and some small-nuclear RNA

A

RNA polymerase II

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

This type of RNA polymerase is found in the nucleus and synthesizes tRNA and some rRNA

A

RNA polymerase III

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

During post transcriptional modifications, exons are _____

A

The part of the sequence that codes for important information and is kept to turn into mRNA

17
Q

During post transcriptional modifications, introns are _____

A

The unimportant part of the sequence that’s spliced and thrown out

18
Q

What is the purpose of spliceosomes and small nuclear RNA?

A

They separate introns and bind the exons together

19
Q

Transcription factors help RNA polymerase find this location, which is the site where transcription begins

A

Promoter

20
Q

RNA polymerase travels down the _ to _ end so that the strand is transcribed in the 5 to 3’ direction

A

3 to 5’

21
Q

For eukaryotes, transcription occurs in the ___ while translation occurs in the ____

A

Nucleus

Cytoplasm

22
Q

This site on the ribosome is responsible for holding the incoming tRNA complex so that the next AA can be added without the strand being displaced

A

A site

23
Q

This site on the ribosome is responsible for holding the tRNA creating the polypeptide bond, so that the polypeptide is created as the chain passes through this site and to the A site

A

P site

(P for Polypeptide creation)

24
Q

This site on the ribosome is responsible for holding the inactivated tRNA before it leaves the ribosome, and also unbinds the mRNA from the ribosome

A

E site

25
Q

During this phase of translation, small RNA subunits bind at the 5’ cap while the tRNA binds the start codon

A

Initiation

26
Q

During this phase of translation, AA’s are added via the P, A and E sites, ultimately forming the polypeptide chain

A

Elongation

27
Q

This phase of translation begins when the stop codon moves into the A site, causing release factors to bind, which then adds H2O to the polypeptide chain and allows peptide transferase and transcription factors to hydrolyze from the tRNA, followed by the polypeptide being released from the P site

A

Termination

28
Q

How do transcription and translation differ in prokaryotes and eukaryotes?

A

In prokaryotes, transcription and translation can occur at the same time, with both happening in the cytoplasm. In eukaryotes, transcription takes place in the nucleus while translation takes place in the cytoplasm, and both have to occur at separate times

29
Q

This structure is a cluster of genes in a prokaryote that share a promoter because they all transcribe for the same thing

A

Operon

30
Q

This type of operon acts like a competitive inhibitor. It only produces genes when needed, because the repressor and operator are bound together, so the repressor has to be pulled off the operating site before it is able to transcribe anything (ex: the lac operon)

A

Inducible

31
Q

This type of operon is in constant protein production, but acts with negative feedback. The repressor is inactive until a corepressor binds to it, and this corepressor is often the product the operon is creating (ex: the trp operon)

A

Repressible

32
Q

These factors are transcription activating proteins that look for specific sections of DNA

A

Transcription factors

33
Q

This domain on the transcription factor binds to the specific DNA sequence

A

DNA binding domain

34
Q

This domain on the transcription factor acts like a scaffold in which more transcription factors can bind and control the extent to which a gene is activated/transcribed

A

Activation domain

35
Q

This type of gene amplification acts like a hub where many different factors can bind to their own receptors to activate the same gene and enhance transcription rate. Example of things that bind include hormones like estrogen and cortisol, and cAMP

A

Enhancers

36
Q

This type of gene amplification occurs when genes are duplicated either on the same chromosome (so that many replicas are made in a row) or by helicase opening specific parts of DNA)

A

Gene duplication

37
Q

How does acetylating or deacetylating histone allow for gene expression to be regulated?

A

Acetylating histones decreases their attraction to DNA (since they become less positive), which means the chromatin unwind a little and create more room for transcription. Similarly, deacetylating histone creates a stronger bond between the histones and DNA, so there will be less room for transcription to occur

MCAT Biochem (9 decks)

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