ch 10 Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

The synthesis of an RNA copy of a gene is called:

A

transcription

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

The process of synthesizing a specific polypeptide on a ribosome is known as:

A

translation

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

In bacteria, transcription and translation occur in the

A

cytoplasm

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

an ____ be broadly defined as a unit of heredity.

A

gene

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

The ______ that constitute the genetic material provide a blueprint for the characteristics of every organism.

A

genes

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

ncRNAs are RNAs that do not encod

A

polypeptides

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

In transcription, a(n)—– sequence is copied into a(n) ——sequence.

A

DNA, RNA

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

During the process of

____ an RNA copy of a gene is produced.

A

transcription

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

An mRNA molecule is used to synthesize a specific polypeptide on a ribosome in the process of

A

translation

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

In eukaryotes, transcription occurs in the ——– whereas translation takes place in the—–

A

nucleus, cytosol

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

Which region of a bacterial gene signals the end of transcription?

A

Terminator

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

The characteristics of an organism are rooted in the activities of cellular ________ encoded by genes.

A

Proteins

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

Transcription occurs in three stages: initiation

A

elongation and termination

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

In the process of ,______ a DNA sequence is copied into an RNA sequence.

A

Transcription

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

The DNA strand that is complementary to the RNA strand produced during transcription is called the ____ strand.

A

Template

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

What sequence of RNA will be transcribed from a DNA template strand that is 5’-ACGTAAC-3’?

A

3’-UGCAUUG-5’

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

Which region of a structural gene signals the beginning of transcription?

A

Promotor

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

Transcription is similar in prokaryotes and eukaryotes, except that ____

A

Eukaryotes involve greater complexity of proteins

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

Before leaving the nucleus, pre-mRNA transcripts are modified by splicing, as well as the addition of _____ and ______ to ends of the mRNA

A

cap and tail

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

Before leaving the nucleus, pre-mRNA transcripts are modified by splicing, as well as the addition of _____ and ______ to ends of the mRNA

A

cap and tail

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

The strand of DNA that is used by RNA polymerase during transcription is called the _____ strand

A

Template

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

In eukaryotic mRNAs, the 5’ cap functions in all of the following EXCEPT

A

Removal of introns from the mRNA

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

The sequence of a DNA template is 3’-GGTTCCTT-5’. What is the sequence of the RNA molecule that will be transcribed from this template strand?

A

5’-CCAAGGAA-3’

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

n mRNA molecule is used to synthesize a specific polypeptide on a ribosome in the process of

A

Translation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

A long poly A tail aids in the export of mRNAs from the:

A

nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How does transcription differ in prokaryotes and eukaryotes?

A

Eukaryotic transcription requires more proteins.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

The introns found in eukaryotic pre-mRNA are removed by a large complex called the

A

spliceosome

28
Q

How are eukaryotic mRNAs modified before leaving the nucleus?

A

Introns are removed by splicing.
A poly(A) tail is added to the 3’ end.
A cap is added to the 5’ end.

29
Q

What is the role of the 5’ cap on a eukaryotic mRNA molecule?

A

It facilitates the exit of mRNA from the nucleus.

It allows the mRNA to bind to a ribosome for translation.

30
Q

There are ____ nucleotide bases are in one codon.

A

3

31
Q

What amino acid is specified by the start codon?

A

Methionine

32
Q

What are the functions of the poly A tail on a mature eukaryotic mRNA?

A

It stabilizes the mRNA.

It aids in the export of mRNA from the nucleus.

33
Q

The start codon defines the reading frame of a(n) , ____ and refers to the order in which codons are read during translation.

A

mRNA

34
Q

What is the name of the complex that removes introns from eukaryotic pre-mRNA molecules?

A

Spliceosome

35
Q

How is an mRNA sequence used to produce a specific amino acid sequence?

A

A codon on mRNA base pairs with an anticodon on a tRNA that carries the appropriate amino acid.

36
Q

The _____ in tRNA binds to a codon in an mRNA.

A

anticodon

37
Q

The genetic code is read in groups of three nucleotide bases known as

A

codons

38
Q

Which RNA molecule functions as an intermediary between an mRNA codon and an amino acid

A

The tRNA

39
Q

The start codon encodes the amino acid

A

Methionine

40
Q

Nirenberg and Leder deciphered the genetic code by synthesizing synthetic ______, molecules and analyzing the polypeptides that were produced.

A

mRNA

41
Q

The reading frame of an mRNA refers to the

A

the order in which codons are read during translation

42
Q

Match each component of the translation machinery with its function.

  1. mRNA
  2. tRNA
  3. Ribosome
  4. Translation
A
  1. mRNA- Contains information needed to synthesize a polypeptide
  2. tRNA- Binds to a codon and carries the appropriate amino acid to be added to the polypeptide
  3. Ribosome- catalyzes the formation of peptide bonds to synthesize a polypeptide
  4. Translation Factor- Proteins required for translation
43
Q

A messenger RNA sequence can be translated into a specific amino acid sequence because _____ RNA molecules base pair with mRNA codons and are attached to specific amino acids.

A

transfer

44
Q

Place the steps of charging a tRNA molecule in the proper sequence.

A
  1. A specific amino acid and ATP bind to aminoacyl-tRNA synthetase
  2. The amino acid is activated by the covalent bonding of AMP, and pyrophosphate is released
  3. The correct tRNA binds to the aminoacyl-tRNA synthetase
  4. The amino acid is covalently attached to the tRNA, and AMP is released
  5. The charged tRNA is released from the aminoacyl-tRNA synthetase
45
Q

Cloverleaf pattern with three stem-loops

Acceptor stem for amino acid attachment

A

Anticodon

46
Q

The _____ molecule is attached to an amino acid and has an anticodon that can base pair with a codon.

A

tRNA

47
Q

Translation occurs on structures called .

A

ribosomes

48
Q

How did Nirenberg and Leder experimentally demonstrate the relationship between mRNA triplet sequences and amino acid sequences?
Multiple choice question.

A

They synthesized synthetic RNA molecules with specific base sequences and analyzed the resulting polypeptides.

49
Q

An ___ is composed of structures called the large and small subunits.

A

ribosome

50
Q

The three major types of RNA are involved in translation. The information to synthesize a polypeptide sequence is contained in

A

mRNA, tRNA and rRNA

51
Q

The ribosomal subunits contain two types of macromolecules:

A

proteins, and RNA

52
Q

The structural features common to all transfer RNAs include a stem-loop containing an___ that is complementary to the codon on mRNA and an acceptor stem where an___ can be attached

A

anticodon; amino acid

53
Q

During the process of charging a tRNA molecule, the enzyme aminoacyl-tRNA synthetase

A

first activates an amino acid using ATP, and then binds a tRNA and transfers the amino acid to it

54
Q

During the initiation stage of translation, an mRNA molecule, the first ___ molecule, and the ribosomal subunits associate. During elongation, ____ bonds are formed between amino acids. Finally, translation ends when the ribosome reaches an ____ codon.

A

tRNA, peptide, stop

55
Q

What is the site of translation?

A

c. Ribosome

56
Q

What are the two subunits of a ribosome called?

A

Large and small subunits

57
Q

During the initiation phase of translation, a complex is formed between an mRNA molecule, the ___ and ____ subunits

A

tRNA and ribosomal

58
Q

Which macromolecules are found in ribosomes?

A

RNA

protein

59
Q

n eukaryotic species, the initiation phase of translation differs in two ways from the process in bacteria. First, instead of a ribosomal-binding sequence, eukaryotic mRNAs have a ________ cap at their 5’ end. Secondly, in eukaryotes, the location of ________ codons is more variable.

A

cap, start, methionine

60
Q

The ___ stage of translation involves the covalent bonding of amino acids to each other, one at a time.

A

Elongation

61
Q

Match each stage of translation with the key events that occur during that stage.

A
  1. Initiation- The mRNA, tRNA, and ribosomal subunits are assembled
  2. Elongation- Peptide bonds are formed between amino acids to synthesize a polypeptide
  3. Termination- A release factor binds to the A site of the ribosome
62
Q

What molecules must assemble during the initiation stage of translation?

A

ribosomal subunits
the first tRNA
mRNA molecule

63
Q

In the process of protein synthesis, what recognizes the three stop codons?

A

A protein called release factor

64
Q

How does the initiation phase of translation differ between eukaryotic and bacterial species?

A
  • The location of the start codon is more variable in eukaryotic species.
  • In eukaryotes, the initiator tRNA carries a methionine, not formyl-methionine
  • Eukaryotic mRNAs have a cap at the 5’ end that facilitates binding to the ribosome.
65
Q

Identify the stage of translation in which polypeptide synthesis occur

A

Elongation

66
Q

During translation, the stop codons are recognized by a protein called a

A

Release Factor