BioBioChem 5 Molecular Genetics Flashcards
(130 cards)
1
Q
defn DNA Genome
A
all of the DNA in the organism
2
Q
Nuclear Genome has ___ chr
A
23
3
Q
Mitochondrial genome has ____ _____ chromosome
A
1 circular chromosome
4
Q
Mitochondrial genome is inherited by the ____
A
mom
5
Q
Zygote (___loid, __n_
A
diploid, 2n
6
Q
Cell cycle is G1 to ___ to G2 to ___
A
G1,S,G2,M
7
Q
What part of the cell phase are most cells hanging out?
A
G1 (growth phase)
8
Q
What is the S phase?
A
DNA rep
9
Q
G2
A
Growth
-get big to divide
10
Q
M phase
A
mitosis, meiosis
11
Q
Defn DNA methylation
A
add CH3 to cytosine (C)
12
Q
DNA methylation triggers gene ____ which means there is __ gene expression and causes heterochromatin formation and prevents transcription proteins from binding
A
silencing, no
13
Q
histones proteins are ____charged and are a ___ concentration of amino acids (___ and ____)
A
positively, high, Arg (R), Lys (K)
14
Q
DNA has a ___ charge because it has a ___ group
A
negative, phosphate
15
Q
Heterochromatin is when we have ______ wound DNA around histones. (called _____)
A
tighlty, nucleosome
16
Q
Defn Nuclesome
A
DNA around histone
17
Q
Heterchromatin means there is no gene expression b/c…
A
DNA is inaccessible
18
Q
We can add acetly groups to the histones which ____ off DNA from histones because they are ___ the charge
A
loosen, neutral
19
Q
Histone acetylation forms ____
A
euchromatin
20
Q
How do we get the DNA to loosen off the histones (euchromatin)
A
Histone acetylation
21
Q
Euchromatin can have gene expression T/F
A
T
22
Q
DNA methylation forms ___
A
heterochromatin
23
Q
Histone acetylation forms ___
A
euchromatin
24
Q
I can alsoform heterchromatin by ____ of histones
A
DEacetyaltion
25
I can also form euchromatin by ___ of DNA
DEmethylation
26
You can also methylate and phosphoylate the histone but must test for whether is forms heterchromatin or euchromatin
27
Between primary mRNA and mature mRNA there is ___ ______
RNA processing
28
RNA processing only occurs in ___ cells
Euk
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Noncoding RNA exs (5)
tRNA
rRNA
SiRNA and MiRNA
SnRNA
30
promoter
where RNA polymerase binds
31
the coding strand is the ___ sequence as the RNA made except T is __
exact, U
32
A binds to __ in RNA
U (instead of T)
33
parts of the coding mRNA
1. 5' UTR (untranslated region)
2. exons (codons)
3. introns (optional in a gene, removed before translation)
4. 3' UTR
34
Introns are optional in a gene and are removed before ____
translation
35
How many bonds are there between A and U
2
36
How many bonds are there between C and G
3
37
RNA processing can also be called
post-transcriptome control
38
RNA processing is only in __ cells and is only for __ mRNA
euk, coding
39
What is the first step in RNA processing?
adding a 5' cap (7-methylguanosine cap)
40
What does adding a 5' cap do?
stability. (decreases mRNA breakdown)
40s ribosome (small unit) bind to start translation
41
What is the 2nd step of RNA processing?
add 3' poly A tail (~300 A's)
42
What is the purpose of adding a 3' poly A tail
stability, role in translation
43
Splicing is when I remove RNA ____
introns
44
splicing (remove RNA introns) changes the seq to create the final mRNA to create ___ coding
protein
45
Alternative splicing is when we remove __ and some specific ____
introns, exons
46
Alternative splicing allows us to use the same DNA the same primary mRNA and results in a different ___
protein
47
mRNA is exported from the ___ to the ___
nucleus, cytosol
48
mRNA in the cytosol make ___
protein/peptide
49
exons/codons/coding region/open reading frame
50
Start Codon
AUG
51
AUG is for ___
Met (M)
52
What is the first amino acid in every protein?
Met
53
What are the three stop codons?
UAA, UGA, UAG
54
At the stop codon the __ ___ binds, and the __ leaves
release factor, ribosome
55
The ___s ribosome binds at the ___ cap and looks for ___
40s, 5' cap, AUG
56
5' cap is the backwards __
G
57
the ___s ribosome binds the AUG
60s
58
Downstream always means toward the __' end
3'
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Create peptide bonds as _____/____ with anticodon binds mRNA codons
tRNA/aa
60
Protein modification is called a post-______ mod
translational
61
DNA polymers are constructed from 4 ______, each consisting of a ____ group, _________ sugar and a ______ base
nucleotides, phosphate, nitrogenous
62
Purines
PURE AG
63
G has an ____ on a ring
oxygen (G looks like an O)
64
Pyramide
cut py once (C,T,U). One ring
65
Mutation for DNA where c-> is because of
deamination (loss of NH2)
66
How can we distinguish DNA and RNA? which carbon
the 2nd carbon
If it is an H it is a deoxyribose
if it is a OH ribose (RNA)
67
Nuceloside
Nitrogenous base attached to a ribose sugar
68
Nucleotide
Nuceloside + phsophate group
69
Does G and C have a higher melting point or A and T
G and C because they have 3 hydrogen bonds
70
what enzymes unwinds DNA?
topoisomerase
71
Prokaryotes have ____ origin of replication in a ____ chromosome
1, circular
72
Lagging strands are also called _____ and are ________ replication
okazaki fragments, discontinuous
73
_ sites for leading strands and __ sites for lagging strands
2, 2 (bidirectional)
74
Helicase unwinds DNA strands (break __-bonds)
H-bonds
75
Single stran binding proteins (SSC) keep ____
2 strands apart
76
Leadings strands are made going ____ the fork
towards
77
DNA pol III
new synthesis
78
DNA pol I
has 3-5' exonuclease for proofreading. It also has a 5-3' exonuclease to remove RNA primers and replace with DNA
79
What enzyme remoes RNA primers
DNA pol I
80
DNA ligase
seals the gap
creates phosphodiester bond b/w 2 DNA fragments
81
Fidelity also means
accuracy
82
The ends of euk chromosomes are called ___
telomeres
83
Telomerase (which lengthens telomeres) is active in (4)
fetus, stem cells, germ line cells, cancer
84
A gene codes for the production of an ____ prodict
RNA
85
rRNA
(ribosomal) RNA component of a ribsosome
-bind mRNA and hold in place in ribosome
86
tRNA
transfer RNA
-bring an aa into the ribosome, tRNA anticodon binds the mRNA codon
87
what two RNA are involved in translation
rRNA and tRNA
88
siRNA and miRNA decide if ____ is translated
mRNA
89
RNA can exit the nucleus, DNA ---
cannot, remains in the nucleus
90
TATA box is an AT rich area beacuse it makes it easier because it has __ bonds
2
91
What types of compounds have RNA and protein?
Ribosome and splicesome
92
snRNPs + snRNA is the ___
spliceosome
93
Lariat
the removed sequence (most times made of introns)
94
Splicing. What are the two rxns?
1st attack is the 5' splice side (upstream)
2nd attack: attack of 3' splice site (downstream)
95
Unambiguous
a codon codes for an amino acid (very specific)
96
Degenerative
one amino acid may have more than one 3 nucelotide (Proline) (CCC,CCG,CCA,CCU)
97
What is the third position in the amino acid called?
wobble
98
Wobble
the third nucleotide can loosely bind wrong base (this is okay for degenerative)
99
Universal
nearly every living organism uses the same genetic code
100
What are the 3 stop codons?
UAA - u are annoying
UGA - u go away
UAG - u are gone
101
prok have a sedimentation co-efficient of ___ and ___ with a total of
30s and 50s (70s)
102
Euk has a sedimentation co eff of __ and __ with a total of ___
40s 60s 80s
103
shine Dalgarno sequence
SD boc at the 5' UTR in prokaryptes
104
The A site is where new ____ with amino acid enters
tRNA
105
40s binds 5' cap, scan to AUG. @AUG, initiator tRNA bind, large subunit binds, new tRNA in A site
106
Secretory pathway is from the ___ to the _____ to the plasma membrane via _______
RER, Golgi, plasma membrane
107
DNA mutations are ___stranded DNA changes
double
108
Silent point mutation
single nucleotide is changed but has no effect because it is the same aa
109
Missesne point mutation
a change in one nucleotide and causes a diff aa
110
Nonsense point mutation
one nucletode change causes the codon to be a stop codon
111
Frameshift mutations result from ___ or ___ of nucelotides in multiples other than 3
deletion, insertion
112
Forward mutation will change the gene even ___ from its original change
more
113
most mutations are ___
neutral
114
Translocation is moving )))) to another chromosome
dsDNA
115
Proto-oncogenes are ____ oncogenes are not
normal
116
Oncogenes only need one copy to be gas pedal are are called a ____ function gene
gain of function gene
117
A tumor suppressor gene is a gene whose product normally ____ the cell from unrestricted growth
protects
118
Both copies must be nonfunctional to get cancer for which gene?
tumour suppressor gene
119
How many chromosomes do humans have and what is their shape?
23 per genome x 2 = 46 and they are linear
120
How are autosomal chromosomes organized?
largest to smallest
121
XX is ___ XY is ___
female, male
122
Tuner's syndrome is ___
XO
123
Kleinfelters is _ _ _
XXY
124
a karyotpe is taken at which phase in mitosis?
metaphase
125
2 chromosomes is 4 ____
chromatids
126
what are common epigenetic changes? 2
DNA methylation
Histone modification: acetylation, methylation, phosphorylation
127
what happens at each stage?G1, S, G2, mitosis
Growth, DNA rep, get bigger to divide, divide DNA
128
Cytokinesis is when the cell ____
pinches into 2 different cells
129
Prophase: DNA ____
condenses
130
