Lecture 6 From DNA to protein Flashcards
(112 cards)
1
Q
What are the nucleotides in DNA?
A
Adenine, thymine, cytosine, guanine
2
Q
What makes up proteins?
A
Amino acids
3
Q
What makes up proteins?
A
Amino acids
4
Q
What does the sequence of amino acids determine of a protein?
A
Structure and function
5
Q
What are the two types of proteins that amino acids make up?
A
Structural proteins, enzymes
6
Q
What is a genome?
A
complete set of genetic information
7
Q
A genome is made of what?
A
chromosome plus plasmids
8
Q
All cells have what genome?
A
DNA
9
Q
Viruses may have ____ genome
A
RNA
10
Q
What are the two tasks that cells must accomplish to multiple?
A
DNA replication, Gene expression
11
Q
What is transcription
A
Information in DNA is copied into RNA
12
Q
What is translation?
A
RNA is used to synthesize proteins
13
Q
How does information flow?
A
DNA to RNA to protein
14
Q
in DNA, what is numbered?
A
carbon atoms of pentose sugar
15
Q
Nucleotides joined between ____ and ____
A
5’PO4 and 3’OH
16
Q
What do nucleotides in DNA form?
A
sugar phosphate backbone
17
Q
What ends does a single DNA strand have?
A
5’ and 3’
18
Q
Strands are ________ which are held together by ________ bonds between nucleobases
A
complementary
hydrogen
19
Q
What are the base pairings?
A
Adenine to thymine (2 H bonds)
Cytosine to Guanine (3 H bonds)
20
Q
Strands are ________, oriented in opposite directions
A
Anti parallel
21
Q
RNA has ________ instead of deoxyribose
A
ribose
22
Q
RNA has ________ instead of thymine
A
Uracil
23
Q
What is RNA shape?
A
Short, single strand
24
Q
In RNA, what replaces thymine?
A
Uracil
25
Uracil pairs with what in RNA?
Adenine
26
RNA molecules is like the _______
transcript
27
What are the three types of RNA?
Messenger RNA
Ribosomal RNA
Transfer RNA
28
Which RNA goes through translation to make a protein?
mRNA
29
DNA replication usually bidirectional from _______ of replication
Origin
30
Two _______ meets at terminating site when process is complete
Replication forks
31
Replication is _______
Semiconservative
32
In DNA replication, what two things bind to the origin of replication?
DNA gyrase and helicases
33
What do DNA gyrase and helicases do?
break and unwind DNA helix
expose single stranded region that can act as a template
34
What RNA enzyme is ABSOLUTELY needed for DNA synthesis?
Primase RNA polymerase
35
What does Primase RNA polymerase do?
synthesizes short regions of RNA called primers
36
Many enzymes form assembly lines called _______
Replisomes
37
What direction does DNA polymerase synthesize in?
5' to 3'
38
What powers the DNA polymerase to synthesize?
The hydrolysis of a high energy phosphate bond
39
DNA polymerase can ONLY _______ nucleotides, not _______
Add, initiate
40
Why are RNA primers required at the origin of replication?
Gives DNA polymerase a molecules to ADD nucleotides to
41
When helicases unzip DNA, it reveals _______
Template sequences
42
in helicase unzipping, _______ strand is synthesized continuously
Leading
43
Spicing removes segments of _____
Eukoryotic transcript
44
non coding intervening sequences are what
Introns
45
in splicing, introns are _____
Removed
46
Expressed regions called _____ remain after introns are removed
Exons
47
Eukoaryotic mRNA produced within membrane bound nucleus must be transported to _____
Cytoplasm
48
Translation cannot _____ during transcription
begin
49
mRNA is _____
Monocistronic
50
Translation begins at the first _____
AUG
51
Ribosomes composed of what subunits?
40s and 60s
52
A set of regulated genes transcribed as single mRNA along with its control sequences is called
Operon
53
Lac operon means what
Lactose metabolism
54
Separate operons controlled by single regulatory mechanism constitute _____
Regulon
55
_____ is simultaneous regulation of numerous genes
global control
56
_____ enzymes synthesize constantly
Constitutive
57
Constitutive enzymes typically have indispensible roles in _____ _____
central metabolism
e.g. enzymes of glycloysis
58
In helicase unzipping, the ________ is synthesized discontinuosly
Lagging
59
DNA can only add nucleotides to ________ end
3'
60
Different DNA polymerase replaces ________
Primers
61
________ forms covalent bond between adjacent nucleotides
DNA ligase
62
Lagging strand produces ________
Okazaki fragments
63
DNA gyrase
Enzyme that temporarily breaks strands of DNA, relieves tension caused by unwinding two strands
64
DNA ligase
Joins two DNA fragments by formaing COVALENT bond between sugar and phosphate of adjacent nucleotides
65
DNA polymerase
Synthesizes DNA, uses one strand as template to make the other
66
Synthesis always occurs in what direction?
5' to 3'
67
What are helicases
Enzymes that unwind DNA helix at replication fork
68
What is okazaki fragment
Nucleic acid fragment produced during discontinuation synthesis of lagging DNA strand
69
What is origin of replication
Region of DNA where replication is initiated
70
What is primase
Enzyme that synthesizes small fragments of RNA to serve as primers for DNA synthesis
71
What is primer
fragment of nucleic acid to which DNA polymerase can add nucleotides
- can only add to existing fragment
72
What is replisome
Complex of enzymes and other protein that synthesize DNA
73
Replication produces how many complete copies of DNA?
two
74
Cell can initiate another round of replication BEFORE
previous round is complete
75
Each daughter cell inherits how many chromosomes already undergoing replication?
One
76
What happens in transcription?
RNA polymerase synthesizes single stranded RNA (mRNA) from DNA template
77
RNA polymerase binds to ________
Promoter
78
What direction does RNA polymerase synthesize in?
5' to 3'
(orientation of newly synthesized strand)
79
Transcription stops at a sequence called
Terminator
80
What polymerase DOES not need a primer?
RNA polymerase
81
RNA sequence is ________ and ________ to DNA template strand
Complementary, antiparallel
82
DNA template is + or - strand
-
83
Complement is + or - strand
+
84
RNA has the same sequence as what DNA strand?
+ DNA strand except Uracil instead of thymine
85
What is the prokaryotic mRNA transcript of one gene?
Monocistronic
86
What is the prokaryotic mRNA transcript of multiple genes?
Polycistronic
87
Proteins encoded on polycistronic message generally have ________ functions
Related
88
What orients the direction of transcription
Promoter
89
Promoter is found ________ of genes
upstream
90
Once RNA polymerase has moved beyond promoter, what happens?
another RNA polymerase can bind
91
When RNA polymerase has moved beyond the promoter, another polymerase can bind
- this allows ________ and ________ transcription
Rapid, repeated
92
What recognizes promoter?
sigma factor
93
synthesis of sigma factors controls what?
transcription of sets of genes
94
what cells use transcription factors to recognize promoters instead of sigma factors?
eukaryotic, archaea
95
When is transcription initiated?
When RNA polymerase binds to promoter
96
What are the major components of the process of decoding information in mRNA?
mRNA, ribosomes (rRNA), tRNAs, accessory proteins
97
mRNA is what?
temporary copy of genetic information
98
Cell must decode the information imbedded in linear array of ________ nucleotide sequence; translating them into the ________ sequence contained in a protein
Nucleotide, amino acid
99
Genetic code is how many nucleotides?
3
100
What is 3 nucleotides also called?
Codon
101
What is a codon the same as?
amino acid
102
What are the three stop codons?
UAA, UAG, UGA
103
What is the start/methionine codon?
AUG
104
What defines the coding region?
nucleotide sequence
105
Ribosomes serve as
Translation machines
106
What do ribosomes do?
aligns and forms peptide bond between amino acids
107
Ribosomes located ________ sequences on mRNA
begins at start site, moves in 5' to 3' direction
punctuation
108
Prokaryotic comprised of ________ and ________ subunits
30S and 50S
109
How many reading frames are possible?
3 reading frames AKA ways in which triplets of nucleotides can be grouped
110
What do tRNAs do?
deliver correct amino acid
111
Each tRNA has a specific ________ sequence, base-pairs with codon
- each carries appropriate amino acid specified by codon
- after delivering amino acid, tRNA can be ________
anticodon
recycled
112
Which direction does the anticodon of tRNA go in?
3' to 5'
