Brainscape's Knowledge GenomeTM

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


See full index

AP Biology Semester 1 > Chapter 17 > Flashcards

Chapter 17 Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

gene expression

A

the process by which DNA directs protein synthesis, two stages: transcription and translation

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

information content of DNA is in the form of _____ _____ of _____

A

specific sequences of nucleotides

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

The DNA inherited by an organism leads to specific traits by….

A

dictating the synthesis of proteins

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

RNA is the bridge between ____ and ____ for which they code

A

genes and proteins

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

transcription

A

the synthesis of RNA under the direction of DNA

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

Translation

A

the synthesis of a polypeptide using information in the mRNA

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

Ribosomes

A

the sites of translation

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

in a eukaryotic cell, the nuclear envelope separates _____ from _____

A

transcription and translation

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

in prokaryotes, _____ of mRNA can begin before ____ has finished

A

translation

transcription

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

primary transcript

A

the initial RNA transcript from any gene prior to processing

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

central dogma

A

the concept that cells are governed by a cellular chain of command: DNA -> RNA -> protein

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

how many amino acids are there?

A

20

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

how many necleotide bases are in DNA

A

4

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

triplet code

A

a series of nonoverlapping, three-nucleotide words… the flow of information from gene to protein is based on these triplet codes

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

The words of a gene are transcribed into complementary nonoverlaping three-nucleotide of words of ____
—these words are then translated into a chain of ____ ___, forming a polypeptide

A

mRNA

amino acids

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

template strand

A
  • happens during transcription
    • provides a template for ordering the sequence of complementary nucleotides in an RNA transcript
  • **the template strand is always the same strand for a given gene
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

codons

A

during translation, the mRNA base triplets are codons (read in the 5’ to 3’ direction)

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

each codon specifies the ____ _____ to be placed at the corresponding position along a polypeptide

A

amino acid

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

how many triplets signal for “stop” to end translation

A

3 triplets

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

true or false:

genetic code is nearly universal, shared by the simplest bacteria to the most complex animals

A

true

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

what is the first stage of gene expression

A

transcription

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

RNA polymerase

A

RNA synthesis is catalzyed by RNA polymerase which pries the DNA strands apart and hooks together the RNA nucleotides

  • RNA is complementary to the DNA template
  • RNA synthesis follows same base pairing other than thymine is now uracil
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

promoter

A

the DNA sequence where RNA polymerase attaches

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

terminator

A

the sequence signaling the end of transcription

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

transcription unit

A

the stretch of DNA that is transcribed

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

what are the three stages of transcription

A
  1. initiation
  2. elongation
  3. termination
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

start point (transcription in eukaryotic cells)

A

promoters signal this trancriptional start point and usually extend several dozen nucleotide pairs upstream of the start point

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

transcription factors

transcription in eukaryotic cells

A

mediate the binding of RNA polymerase and the initiation of transcription

29
Q

Transcription initiation complex

transcription in eukaryotic cells

A

the completed assembly of transcription factors and RNA polymerase bound to a promoter…this is transcription initiation complex

30
Q

TATA box

transcription in eukaryotic cells

A

a promoter.. crucial in forming the initiation complex in eukaryotes

31
Q

in transcription the RNA polymerase moves along the DNA, it ____ the double helix

A

untwists

32
Q

nucleotides are added to the _’ end of the growing RNA molecule in transcription

A

3’

33
Q

how does termination work in bacteria versus eukaryotic

A

bacteria: stops transcription at the end of the terminator and mRNA can be translated without further modification
eukaryotes: RNA polymerase transcribes the polyadenylation signal sequence; The RNA transcript is released 10-35 nucleotides past this polyadenylation sequence

34
Q

what do eukaryotic cells do the RNA after transcription?

A
  1. enzymes in eukaryotic nucleus modify pre-mRNA before the genetic messages are dispatched to the cytoplasm
  2. During RNA processing, both ends of the primary transcript are altered
  3. some interior parts of the molecule are cut out, and others are spliced together
35
Q

what does the 5’ end get in mRNA

what does the 3’ end get in mRNA

A
  • 5’ cap

- 3’ poly- A tail

36
Q

what is the functions of these 5’ and 3’ ends

A
  1. facilitate export of mRNA
  2. protect mRNA from hydrolytic enzymes
  3. help ribosomes attach to the 5’ end
37
Q

introns

A

regions that are taken out and will not be expressed

38
Q

exons

A

regions that are eventually expressed and translated into amino acid sequence

39
Q

RNA splicing

A

removes introns and joins exons, creating mRNA molecule

40
Q

what carries out RNA splicing

A

splicesomes

41
Q

ribozymes

A

catalytic RNA molecules that function as enzymes and can splice RNA

42
Q

what are the three properties of RNA enabling it to function as an enzyme

A

– It can form a three-dimensional structure because
of its ability to base-pair with itself
– Some bases in RNA contain functional groups that may participate in catalysis
– RNA may hydrogen-bond with other nucleic acid molecules

43
Q

domains

A
  • proteins have a modular architecture consisting of descrete regions called domains
  • different exons code fro the different domains in a protein
44
Q

genetic information flows from ____ to ___ through the process of translation

A
  • mRNA
  • protein
  • Translation
45
Q

transfer RNA

A

a cell translates an mRNA message into protein “language”

–tRNA transfer amino acids to the growing polypeptide in a ribosome

46
Q

anticodon

A

the anticodon base-pairs with a complementary codon on mRNA

47
Q

accurate translation requires what two steps

A

First: a correct match between a tRNA and an amino acid, done by the enzyme aminoacyl-tRNA synthetase
– Second: a correct match between the tRNA anticodon and an mRNA codon

48
Q

wobble

A

flexible pairing at the third base of a codon is wobble. allows some tRNAs to bind to more than one codon

49
Q

ribosomes

A

-facilitate specific coupling of tRNA anticodons with mRNA codons in protein synthesis

50
Q

what are the two ribosomal subunits made up of?

A

proteins and ribosomal RNA

51
Q

what are the ribosomes three binding sites?

A

P site
A site
E site

52
Q

what is P site?

A

holds the tRNA that carries the growing polypeptide chain

53
Q

what is A site?

A

holds the tRNA that carries the next amino acid to be added on the chain

54
Q

what is E site?

A

the exit site, where discharged tRNAs leave the ribosome

55
Q

what does the initiation stage of translation do?

A

brings together mRNA, a tRNA with the first amino acid, and the two ribosomal subunits

1st: a small ribosomal subunit binds with mRNA and a special initiator tRNA
2nd: the small subunit moves along the mRNA until it reaches the start codon (AUG)
3rd: proteins called initiation factors bring in the large subunit that completes the translation initiation complex

56
Q

what does the elongation stage of translation do?

A
  • amino acids are added one by one to the preceding amino acid at the C-terminus of the growing chain
  • each addition involves proteins called elongation factors and occurs in three steps (1) codon recognition (2) peptide bond formation (3) translocation
  • translation proceeds along the mRNA in a 5’ to 3’ direction
57
Q

what happens in the termination stage of translation

A
  • a stop codon in the mRNA reaches the A site of the ribosome
  • A site accepts a protein called a release factor
  • release factor causes the addition of a water molecule instead of an amino acid
  • this reaction releases the polypeptide, and translation assembly falls apart
58
Q

polyribosome

A

a number of ribosomes that can translate a single mRNA simultaneously

59
Q

during and after synthesis, a polypeptide chain spontaneously ___ and ____ into a _____ ____

A
  • coils
  • folds
  • 3D shape
60
Q

signal peptide

A

polypeptides destined for the ER or for secretion are marked by a signal peptide

61
Q

SRP (signal recognition particle)

A

binds to the signal peptide

-the SRP brings the singal peptide and its ribosome to the ER

62
Q

point mutations

A

chemical changes in just one base pair of a gene

63
Q

what two general categories are there for point mutations

A
  • nucleotide pair substitutions

- one or more nucleotide pair insertions or deletions

64
Q

nucleotide pair substitution

A

replaces one nucleotide and its partner with another pair of nucleotides

65
Q

silent mutations

A

have no effect on the amino acid produced by a codon because of redundancy in the genetic code

66
Q

missense mutations

A

still code for an amino acid, but not the correct one

67
Q

nonsense mutations

A

change an amino acid codon into a stop codon, nearly always leading to a nonfunctional protein

68
Q

frameshift mutation

A

caused by insertions or deletions of nucleotide pairs

69
Q

mutagens

A

physical or chemical agents that can cause mutations

AP Biology Semester 1 (21 decks)

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