Central Dogma (LAB) Flashcards
1
Q
scientists that unraveled the molecular structure of DNA
A
James Watson
Francis Crick
Maurice Wilkins
2
Q
genetic material and capable of transmitting biological information from parents to offsprings
A
DNA
3
Q
the information stored in DNA when translated will result to a particular trait which expressed through the action of ___
A
proteins
4
Q
three processes of central dogma of molecular biology
A
replicaiton
transcription
translation
5
Q
DNA replicates in a ___ mode
A
semi-conservative moed
6
Q
mode of DNA where the newly synthesize molecule contains an old strand from the parent DNA and newly synthesized DNA strand
A
semi-conservative method
7
Q
two strands of parent DNA serves as a ___ or pattern to which a complementary strand is synthesized
A
template
8
Q
the accuracy of replication is guaranteed by specific ___
A
base pairing
9
Q
process where RNA is being synthesized from DNA template
A
transcription
10
Q
three general steps of treanscription
A
initiation
elongation
termination
11
Q
three types of RNA obtained
A
messenger RNA
transfer RNA
ribosomal RNA
12
Q
process where proteins are synthesized
A
translation
13
Q
a ___ chain from the activation of amino acids, initiation and termination of translation to undergo processing becomes a functional protein
A
polypeptide
14
Q
replicate the DNA strand with the following bases
3’ C A G T T A C G G C T C C T A G G T T A T A A T T C G T T T C5’
A
5’ G T C A A T G C C G A G G A T C C A A T A T T A A G C A A A G 3’
15
Q
direction where the parent strand is read
A
3’ to 5’
16
Q
new strand is synthesized in what direction
A
5’ to 3’
17
Q
demonstrate transcription process to with the template below
3’ C A G T T A C G G C T C C T A G G T T A T A A T T C G T T T C 5’
A
5’ G U C A A U G C C G A G G A U C C A A U A U U A A G C A A A G 3’
18
Q
Replication process proteins
A
Helix unwinding protein
Helix Destabilizing protein
Helix relaxing protein
RNA primase
DNA Polymerase III
DNA Polymerase I
DNA Ligase
19
Q
Relieves supercoiling stress ahead of the replication fork by introducing negative supercoils.
A
DNA gyrase
20
Q
Synonymous with helicase, it unwinds the DNA helix at the replication fork.
A
helix unwinding protein
21
Q
helix unwinding protein is also known as
A
helicase
22
Q
Refers to single-strand binding proteins (SSBs) that stabilize unwound DNA strands and prevent them from reannealing.
A
helix destabilizing proteins
23
Q
helix destabilizing proteins are also known as
A
single-strand binding proteins (SSBs)
24
Q
Another term for DNA topoisomerase, which alleviates torsional strain during replication.
A
helix relaxing proteins
25
Synthesizes short RNA primers needed to initiate DNA synthesis.
RNA primase
26
The primary enzyme for synthesizing the new DNA strand in a 5' to 3' direction.
DNA polymerase III
26
Removes RNA primers and replaces them with DNA nucleotides.
DNA Polymerase I
26
Seals gaps between Okazaki fragments on the lagging strand to create a continuous DNA strand
DNA ligase
26
is essential in DNA replication because DNA polymerases, the enzymes responsible for synthesizing DNA, cannot initiate the process on their own. They can only add nucleotides to an existing strand with a free 3' hydroxyl group.
RNA primase
26
- A protein that binds to RNA polymerase and facilitates its attachment to the promoter sequence, ensuring the correct initiation of transcription.
sigma factor
26
A specific DNA region where RNA polymerase binds to initiate transcription; it acts as a "start signal" for gene expression.
promoter sequence
26
Synthesizes ribosomal RNA (rRNA), excluding the 5S rRNA, in eukaryotes.
RNA polymerase I
27
Synthesizes messenger RNA (mRNA) and some small nuclear RNA (snRNA) in eukaryotes. It plays a central role in gene expression.
RNA Polymerase II
28
Synthesizes transfer RNA (tRNA), 5S rRNA, and other small RNAs in eukaryotes.
RNA Polymerase III
29
A protein involved in terminating transcription in prokaryotes. It binds to the RNA strand and disrupts RNA-DNA interaction, halting transcription.
Rho factor
30
Occurs during transcription termination in prokaryotes, often when a sequence forms a hairpin structure that destabilizes RNA polymerase's interaction with DNA.
loop formation
31
- An enzyme that attaches the correct amino acid to its corresponding transfer RNA (tRNA), forming an aminoacyl-tRNA. This ensures accurate translation.
aminoacyl synthethase
32
A protein in prokaryotic translation that facilitates the binding of the small ribosomal subunit to mRNA and stabilizes the initiation complex.
initiation factor (IF-1)
33
A protein that guides the initiator tRNA (bearing methionine in eukaryotes or formyl-methionine in prokaryotes) to the P site of the ribosome.
initiation factor (IF-2)
34
A protein that prevents the premature association of the small and large ribosomal subunits and aids in mRNA alignment on the ribosome.
initiation factor 3 (IF-3)
35
An enzymatic activity of the ribosome's large subunit that forms peptide bonds between amino acids, elongating the polypeptide chain during translation.
peptidyl transferase
36
A sequence in mRNA (UAA, UAG, or UGA) that signals the termination of translation. It does not code for any amino acid and instead recruits release factors to disassemble the translation machinery.
stop codon
37
diagram the products of replication using the DNA molecule below:
3' CAGTTACGGCTCCTAGGTTATAATTCGTTC 5'
5' G T C A A T G C C G A G G A T C C A A T A T T A A G C A A G 3'
38
diagram the products of transcription using the DNA molecule below:
3' CAGTTACGGCTCCTAGGTTATAATTCGTTC 5'
5' G U C A A U G C C G A G G A U C C A A U A U U A A G C A A G 3'
39
diagram the products of translation using the DNA molecule below:
3' CAGTTACGGCTCCTAGGTTATAATTCGTTC 5'
Val - Asn - Ala - Glu - Asp - Pro - Ile - Leu - Ser - Lys
40
the base composition of the DNAs from many organisms, particularly in microorganisms vary, yet the amino acid compositions of the proteins of microorganisms having very different base compositions are very similar, what explanation can you suggest for this observation?
This intriguing observation can be explained by the degeneracy of the genetic code. Here's how it works:
Redundancy in Codons: The genetic code is composed of 64 codons, but these codons encode only 20 standard amino acids. This means multiple codons can specify the same amino acid. For example, the amino acid leucine is encoded by six different codons (UUA, UUG, CUU, CUC, CUA, CUG).
Adaptation to Base Composition: Even if organisms have varying base compositions (e.g., more GC-rich or AT-rich DNA), they can still encode the same amino acids. GC-rich organisms might prefer codons with more guanine (G) and cytosine (C), while AT-rich organisms might favor codons with more adenine (A) and thymine (T). Despite these preferences, the same proteins can be synthesized because of the codon redundancy.
Protein Function and Selection: The similarity in amino acid compositions arises because protein structure and function are under strong evolutionary pressure. The codon usage bias (due to base composition) does not impact the resulting amino acid sequences significantly, as long as the correct proteins are produced.
41
the A-T, G-C ratios of DNA of cattle and rat are very similar, would you expect the tRNAs, rRNAs, and mRNAs of the two species to be similar?
If the A-T and G-C ratios of the DNA of cattle and rats are very similar, it suggests that their overall nucleotide composition is alike. However, when it comes to tRNAs, rRNAs, and mRNAs, there are additional factors to consider:
tRNAs: Transfer RNAs are highly conserved across species because their structure and function (in translation) are critical for life. The similarity in DNA composition might contribute to their similar sequences, but the conservation of function is the primary reason why tRNAs from cattle and rats would be alike.
rRNAs: Ribosomal RNAs are also highly conserved due to their essential role in ribosome function and protein synthesis. While the similarity in A-T/G-C ratios could contribute to comparable rRNA sequences, evolutionary pressures ensure their conservation across species for maintaining ribosomal integrity.
mRNAs: Messenger RNAs would differ more significantly between the two species compared to tRNAs and rRNAs. mRNAs encode proteins, and the protein-coding genes vary based on the distinct physiology and needs of each organism. Even if the DNA base composition is similar, the sequences of mRNAs will reflect the differences in genes expressed in cattle versus rats.
In summary, the similarity in DNA base composition could contribute to some shared features in tRNAs and rRNAs because of their conserved roles. However, mRNAs are expected to differ more substantially due to species-specific gene expression requirements. Let me know if you'd like to explore any aspect of this further!
42
: DNA copies
itself into two identical
strings although copying
errors may occur called
mutation
replication
43
A gene is
converted into an
intermediate sequence of
chemically distinct
nucleotides called an RNA
(different types such as
mRNA, tRNA, rRNA, etc.).
transcription
44
RNA is further
decoded to produce the
functional activity of a gene
which usually takes the form
of a protein.
translation
45
functional activity of a gene
protein
46
copying errors in replication
mutations
47
extension of central dogram
reverse transcription
48
enyzme for RT
RNA-dependent DNA-polymerase
49
enzyme for replication
DNA-dependent DNA-polymerase
50
enzyme for transcription
DNA-dependent RNA polymerase
51
complex process involving ribosomes, tRNAs, and other molecules
translation
52
traits are expressed in ___ action
protein
53
DNA > RNA is due to what reasoning
cell is avoiding the overuse of DNA to risk unnecessary damaged
54
nucleotide sequence of RNA is decoded in an amino acid
Translation
55
proteins that directly affect trait expression
structural proteins
melanin synthesis enzymes
receptor proteins
hemoglobin
56
proteins that indirectly affect trait expression
transcription factors
signal transduction proteins
chaperone proteins
epigenetic regulatrs
57
RNA viruses have what kind of enzyme to replicate itself
RNA replicases
58
Occurs when chromosomes duplicate
before mitosis & meiosis
DNA replication
59
Makes an exact copy of the DNA
DNA replication
60
H bonds between nitrogenous bases break and enzymes "unzip" the molecule during this process
DNA replication
61
DNA which is much less complex than its counterpat
prokaryotic DNA
62
model of prokaryotic DNA
y-fork model
63
first step of DNA replication
unwinding of DNA
64
enzymes present in DNA unwinding
HDP
HUP
DNA gyrase
65
protein in DNA replication where ATP is used to separate parental strand
Helix unwinding protein
66
HUP is also known as
DNA helicase
67
binds to ssDNA at separation fork to prevent repairing of DNA
helix destabilizing protein
68
HDP is also known as
single strand binding protein
69
he process of re-establishing the double-stranded structure of DNA or other molecules that have been separated into single strands, typically through heating
reannealing
70
prevent reannealing of DNA
HDP
71
relax the twisting tension created by the unwinding process
dna gyrase
72
Synthesized continuously in the same direction as the unwinding of the DNA double helix. This is because DNA polymerase works in the 5' to 3' direction, which matches the replication fork's progression on the leading strand.
leading strand
73
Synthesized discontinuously in the opposite direction of the replication fork movement. Short fragments called Okazaki fragments are formed, which are later joined together by DNA ligase.
lagging strand
74
Requires only a single RNA primer at the start of synthesis because it proceeds continuously.
leading strand
75
Needs multiple RNA primers because each Okazaki fragment requires its own starting point.
lagging strand
76
is synthesized in a smooth, uninterrupted fashion as the helicase exposes the template.
leading strand
77
must repeatedly wait for helicase to expose new sections of the template before initiating synthesis of the next fragment.
lagging strand
78
What do you think would
happen if there are no
helix unwinding proteins
and helix destabilizing
proteins?
If helix-unwinding proteins (like helicase) and helix-destabilizing proteins (like single-strand binding proteins, SSBs) were absent, the DNA replication process would be severely disrupted. Here's what might occur:
No Separation of DNA Strands:
Without helicase, the DNA double helix wouldn’t be unwound. The two strands would remain tightly bound by hydrogen bonds, preventing the creation of a replication fork—an essential structure for DNA replication.
Formation of Secondary Structures:
Without SSBs to stabilize the separated strands, the unwound DNA might form secondary structures like hairpins or reanneal (rebind) to itself. This would block DNA polymerase from accessing the template strand for replication.
Halting DNA Synthesis:
Both processes—unwinding and stabilization—are prerequisites for replication. Without them, enzymes like DNA polymerase couldn’t synthesize new strands, halting DNA replication altogether.
Genomic Instability:
A lack of replication would lead to cell division errors. Over time, this could result in genomic instability, leading to cell death or malfunction.
79
second step of dna replication
priming of templates
80
RNA primer is also called
RNA polymerase, primase
81
enzyme that synthesizes a short RNA primer complementary to the DNA template strand.
primase
82
RNA primer provides a free ___ group for DNA polymerase to start adding nucleotides
3'-OH
83
Only __primer is needed for the leading strand, as replication proceeds continuously in the direction of the replication fork.
one
84
___primers are needed for the lagging strand because replication occurs in fragments (Okazaki fragments), which are synthesized discontinuously.
multiple
85
A type of RNA polymerase, primase synthesizes the short RNA primers required to initiate DNA replication.
primase
86
After the primer is synthesized, ____ binds to the primer and begins adding nucleotides to extend the new DNA strand.
DNA polymerase
87
On the lagging strand, ___ joins the Okazaki fragments together after their synthesis.
ligase
88
are short DNA sequences that are synthesized during the replication of the lagging strand.
okazaki fragments
89
importance of priming?
The priming process is crucial for accurate DNA replication, ensuring that new strands are synthesized efficiently and correctly. Without primase and the resulting primers, DNA polymerase could not initiate replication.
90
what direction does DNA elongation happen?
DNA elongation always occurs in the 5' to 3' direction, regardless of whether it is the leading or lagging strand
91
Do you think priming of the
templates is also possible for
the lagging strand? Predict
what would happen during
the priming of the lagging
strand.
Yes, priming of the templates is definitely possible for the lagging strand—it's an essential part of its replication process. However, due to the lagging strand's unique orientation, priming happens repeatedly, creating multiple starting points for DNA synthesis.
92
direction of complementary strand of the lagging strand
3' to 5'
93
third step of DNA replication
elongation of complementary strand
94
___ strand produces one long DNA complement
leading strand
95
___ strands produces short DNA segments (okazaki fragments)
lagging
96
is a critical phase in DNA replication, where new DNA strands are synthesized by adding nucleotides to the existing primer using the original strands as templates
elogation of complementary DNA strand
97
Elongation begins when ___ ____ adds nucleotides complementary to the template strand, extending the newly synthesized strand in the 5' to 3' direction.
DNA polymerase
98
Elongation begins when DNA polymerase adds nucleotides complementary to the template strand, extending the newly synthesized strand in the ___ direction.
5' to 3'
99
strand where DNA elongation is continuous, as it follows the replication fork's movement.
leading strand
100
strand where elongation happens in short segments (Okazaki fragments), as the synthesis direction opposes the fork's progression.
lagging strand
101
Each added nucleotide pairs with the template strand (A with T, G with C). The new nucleotide is attached to the growing strand's 3'-OH group, releasing ___as a byproduct.
pyrophosphate
102
seals the gaps between Okazaki fragments to form a continuous strand.
DNA ligase
103
The primary enzyme responsible for adding nucleotides to the growing DNA strand
dna polymerase
104
type of dna polymerase (in prokaryotes): Main enzyme for elongation
dna polymerase III
105
type of dna polymerase present in eukaryotes that Handle leading and lagging strand synthesis.
DNA polymerase δ (delta) and ε (epsilon)
106
Remove RNA primers during lagging strand synthesis.
Exonucleases
107
RNA primers are digested by ___ exonuclease
3' to 5' (based on miss)
108
What do you think would happen if the cell lose its capacity to synthesize DNA polymerase I?
1. Incomplete Removal of RNA Primers:
DNA polymerase I is responsible for removing RNA primers from Okazaki fragments on the lagging strand through its 5' to 3' exonuclease activity.
Without this enzyme, RNA primers would remain in the replicated DNA, compromising the strand's integrity and stability.
2. Gaps in the DNA Strand:
After removing RNA primers, DNA polymerase I typically fills in the gaps with DNA nucleotides. Without it, these gaps would persist, leaving regions of the strand incomplete.
3. Impairment of DNA Ligase Function:
DNA ligase can only seal the nick in the sugar-phosphate backbone when adjacent fragments are fully DNA. If RNA primers are not replaced, ligase cannot function properly, leading to discontinuities in the lagging strand.
4. Genomic Instability:
Unrepaired gaps and RNA remnants in the DNA could disrupt processes like transcription and replication in future cell cycles, leading to genomic instability.
Over time, this could result in cell dysfunction or death.
109
acts as a proofreader after sealing of breaks
DNA ligase
110
eukaryotic DNA has this protein that prokaryotic DNA does not have
histones
111
Has many initiation sites
what kind of DNA replication
eukaryotic
112
More protein factors are used
eukaryotic DNA replication
113
Dissociation of ___from the DNA then
reassociates after replication
histones
114
Old ___ are conserved and new ones are
synthesized in eukaryotic DNA replication
octamers
115
Each old strand of nucleotides serves as a
template for each new strand.
what kind of replication
semi-conservative replication
116
2 factors that ensure accurate DNA replication
Proofreading ability
of DNA polymerase
Presence of DNA
repair mechanism
in the cell nucleus
117
2 parts of protein synthesis
transcription
translation
118
makes a RNA molecule
complementary to a portion of DNA.
transcription
119
occurs when the sequences of
bases of mRNA directs the sequence of amino
acids in a polypeptide.
translation
120
Carries genetic info from the nucleus to
the cytoplasm
messenger RNA
121
Carries specific amino acids to the
ribosome to build the protein
transfer RNA
122
Major component of the ribosome
organelle
rRNA
123
site of protein synthesis
rRNA
124
most abundant type of RNA
rRNA
125
Prokaryotes, like bacteria, have smaller ribosomes referred to as __ribosomes
70s
126
small subunit
30s
127
large subunit
50s
128
Contains 16S rRNA, which plays a critical role in aligning the mRNA during translation and interacting with transfer RNA (tRNA).
small subunit (30s)
129
Contains 23S rRNA, which forms part of the peptidyl transferase center, catalyzing peptide bond formation.
large subunit
130
Contains 5S rRNA, which helps stabilize the ribosome structure
large subunit
131
which plays a critical role in aligning the mRNA during translation and interacting with transfer RNA (tRNA).
16s rRNA
132
which forms part of the peptidyl transferase center, catalyzing peptide bond formation.
23s rRNA
133
which helps stabilize the ribosome structure.
5s rRNa
134
Eukaryotes have larger ribosomes, known as __S ribosomes, also consisting of two subunits:
80s
135
Contains 18S rRNA, which is involved in recognizing and aligning mRNA during translation.
small subunit (40s) in eukaryotes
136
is involved in recognizing and aligning mRNA during translation.
18s rRNA
137
part of the peptidyl transferase center for peptide bond formation in eukaryotes
28s RNA
138
which associates with 28S rRNA to maintain ribosome structure in eukaryotes
5.8S rRNA
139
view comparison of prokaryotic rRNA and eukaryotic rRNA
+1
140
two functional regions in the ribosome
a site
p site
141
a site stands for
aminoacyl site
142
p site stands for
peptidyl site
143
is where an incoming aminoacyl-tRNA (a tRNA molecule bound to its corresponding amino acid) binds to the ribosome.
a site
144
This is the "acceptor" site for new tRNA molecules during translation.
a site
145
The tRNA at the __ site brings in the next amino acid that corresponds to the codon on the mRNA strand.
A
146
holds the tRNA carrying the growing polypeptide chain.
p site
147
It is the site where peptide bond formation occurs between the amino acid in the A site and the polypeptide chain in the P site.
p site
148
After the peptide bond is formed, the tRNA at the ___ site becomes uncharged (no longer carrying an amino acid) and eventually exits the ribosome.
P
149
As translation progresses, the ribosome moves along the mRNA (a process called
translocation
150
The process by which RNA is
copied from DNA in the
nucleus
transcription
151
first step of transcription
RNA polymerase binds to the promoter section of DNA
152
second step of transcription
DNA unwinds and separates
153
third step of transcription
rna polymerase adds nucleotides complimentary to the DNA template strands
154
fourth step of transcription
process ends once RNA polymerase reaches the termination signal on the DNA
155
can randomly bind to the transcribable site
RNA Polymerase
156
is transcription a continuous process?
no
157
part of DNA strand that is transcribed
transcribable region
158
Transcription begins when the enzyme ___binds to the promoter region of a gene. T
RNA polymerase
159
Transcription begins when the enzyme RNA polymerase binds to the ___region of a gene.
promoter
160
The main enzyme that synthesizes RNA.
RNA polymerase
161
In eukaryotes, additional proteins called ___ ___ help RNA polymerase bind to the promoter and initiate transcription.
transcription factors
162
____ ___unwinds the DNA and starts synthesizing RNA by adding nucleotides complementary to the DNA template strand. This forms a growing RNA chain.
RNA polymerase
163
RNA synthesis occurs in the ___ direction
5' to 3'
164
DNA template in rna synthesis is read in the ___ direction
3' to 5'
165
Transcription ends when RNA polymerase encounters a ___signal on the DNA.
termination signal
166
is a protein subunit of RNA polymerase in prokaryotes that plays a crucial role in the initiation phase of transcription
sigma factor
167
sigma factor that forms a complex with the RNA polymerase core enzyme, creating a
holoezyme
168
can bind specifically to promoters, a capability the core enzyme lacks on its own.
holoenzyme
169
are regions in the DNA that signal the end of transcription.
terminator sequence
170
In prokaryotes, termination can occur by two mechanisms
rho dependent
rho independent
171
Requires a protein called the rho factor, which is an RNA helicase that unwinds RNA-DNA hybrids.
rho-dependent termination
172
A rho recognition site on the RNA (called a
rut site
173
sitethat is rich in cytosine residues and devoid of secondary structures.
rho recognition site
174
When __catches up to RNA polymerase (typically when it stalls at the termination site), rho unwinds the RNA-DNA hybrid, releasing the RNA transcript.
rho
175
oes not require any external proteins like rho factor. Instead, it relies solely on sequences within the RNA transcript.
rho-independent termination
176
Does not require ATP or additional proteins; it's intrinsic to the sequence itself.
rho-independent termination
177
A protein helicase that facilitates rho-dependent termination
rho factor
178
view difference of rho-dependent and independent termination
+1
179
enyzme used to make RNA polymer from DNA
RNA polymerase
180
starting point on DNA
promoter region
181
strand of DNA that RNA is complementary to
DNA template
182
ending point on DNA
termination signal
183
products of transcription
mRNA
tRNA
rRNA
184
products of transcription move out of the ___ into the ___ to be used in protein synthesis
nucleus
cytoplasm
185
non coding segments that are spliced out
intronds
186
kind of RNA that is processed before leaving the nucleus
eukaryotic RNA
187
coding segments
exons
188
the making of proteins at the ribosome
protein synthesis
189
the amount and kind of proteins produced in a cell determine its ___ and __
structure
function
190
the correlation between nucleotide sequence and amino acid sequence
genetic code
191
combination of 3 mRNA nucleotides that code for a specific amino acid
codons
192
total number of codons
64
193
number of codons that specify the 20 amino acids
61
194
how many codons are chain-terminating and do not specify and amino acid
3
195
starts the process of translation
start codon (AUG)
196
start codon
AUG
197
ends the process of translation
stop codons
198
stop codons
UAA UAG
UGA
199
start codon is what protein
Methionine
200
The phenomenon where the third base of a codon shows variability during translation is referred to as the
wobble hypothesis
201
The genetic code is ___, meaning that multiple codons can encode the same amino acid. These synonymous codons often differ only at the third base position.
degenerate
202
During translation, the anticodon of tRNA pairs with the codon on mRNA. While strict Watson-Crick base pairing applies to the first two bases, the third base allows for _____, meaning it can form non-standard base pairings (e.g., G-U or I-A).
wobble pairing
203
increases flexibility and allows fewer tRNA molecules to recognize multiple codons, streamlining the process of protein synthesis.
wobble pairing
204
contributes to the efficiency of translation:
It reduces the need for a unique tRNA for every possible codon.
It provides resilience to mutations at the third base, as these are less likely to alter the encoded amino acid (silent mutations).
wobble mechanism
205
The process of assembling polypeptides
(proteins) from nucleotide sequence in mRNA
translation
206
The final product of gene expression is a
___chain of amino acids whose
sequence was prescribed by the genetic code.
polypeptide
207
__transcribed from genomic DNA
mRNA
208
transport amino acids
tRNA
209
align amino acids attached to tRNA and
create the peptide bonds between adjacent amino acids
rRNA
210
"reads" mRNA
ribosome
211
Two subunits composed of protein
and ribosomal RNA (rRNA)
ribosome
212
ribosome is composed of
protein
ribosomal RNA
213
is a structural component
of the ribosome subunits
rRNA
214
ribosome of eukaryote
80s
215
two subunit of eukaryotic ribosome
40s
60s
216
40s subunit of eukaryote is made up of
18s RNA + 33 proteins
217
60s subunit of eukaryotic ribosome is made up of
28s RNA + 49 proteins
218
the S in the 80S stands for
svedverg unit
219
are small, extremely stable RNA
structures shaped like a cloverleaf due to
internal base pairing
tRNAs
220
amino acid attaches to what end of tRNA
3' end (OH)
221
5' end of tRNA has
P
222
They are almost identical in both prokaryotes
and eukaryotes
tRNA
223
is a small, L-shaped RNA molecule that plays a critical role in protein synthesis by transporting amino acids to the ribosome during translation
tRNA
224
Contains a triplet of bases known as the anticodon, which is complementary to the codon on the mRNA.
anticodon loop
225
ensures the correct amino acid is added to the growing polypeptide chain by aligning the tRNA with the appropriate codon on the mRNA during translation.
anticodon loop
226
Located at the 3' end of the tRNA, which always ends in the sequence CCA
amino acid attachment site
227
amino acid attachment site always begin with
A C C
228
amino acid attachment site is where a specific amino acid is covalently attached by the enzyme
aminoacyl tRNA synthethase
229
Contains modified bases, such as dihydrouridine.
d-loop
230
d-loop stands for
dihydrouridine loop
231
This loop contributes to the folding of the tRNA molecule and interacts with the aminoacyl-tRNA synthetase for proper amino acid attachment.
dihydrouridine loop
232
Contains the conserved sequence TψC (where ψ represents pseudouridine).
T loop
233
ψ represents
pseudouridine
234
This loop interacts with the ribosome, helping the tRNA align properly during translation.
T loop
235
A region of varying size and sequence that lies between the anticodon loop and the TψC loop.
variable loop
236
They contain a number of posttranscriptional
modifications, including non-traditional
bases (other than (A, U, G and C)
tRNA
237
3' to 5' sequence that matches the complementary 5' to 3' sequence on the mRNA
anticodon
238
amino acid on 3' end
acceptor arm
239
provide structure for interface with aminoacyl tRNA synthesis
T an D loops
240
the two subunits of the ribosome come
together and the start codon on the mRNA in the
ribosome is aligned to set the reading frame
what step in translation
initiation
241
—Charged tRNAs attach and peptide
bonds form between the amino acids
what step in translation
elongation
242
ribosome moves from what direction
5' to 3'
243
why is translation more complicated for eukaryotres
Translation is more complicated in eukaryotes compared to prokaryotes due to differences in cellular organization, mRNA processing, ribosome structure, initiation mechanisms, regulation, and additional translational machinery. Eukaryotic cells have compartmentalized processes, with transcription occurring in the nucleus and translation in the cytoplasm, necessitating mRNA transport. Prokaryotic cells, by contrast, allow transcription and translation to occur simultaneously in the cytoplasm. Furthermore, eukaryotic mRNA undergoes extensive modifications, such as the addition of a 5' cap, a poly-A tail, and intron splicing, whereas prokaryotic mRNA requires minimal processing. Eukaryotic ribosomes (80S, consisting of 40S and 60S subunits) are larger and more complex than prokaryotic ribosomes (70S, consisting of 30S and 50S subunits), which makes the machinery itself more intricate. In terms of initiation, eukaryotes rely on a scanning mechanism involving multiple eukaryotic initiation factors (eIFs) to locate the start codon, while prokaryotes use a simpler Shine-Dalgarno sequence for ribosome binding. Additionally, translation in eukaryotes is tightly regulated through mechanisms like microRNAs and interactions with the endoplasmic reticulum for secretory proteins, adding further layers of complexity.
244
view difference in translation for prokarotes and eukaryotes
+1
245
Translation takes place directly after
transcription
in what kind of translation
prokaryotic
246
what kind of translation where mRNA is note modified
prokaryotes
247
Transcription and translation take
place in the same area in what type
prokaryotic
248
Transcript is modified before leaving
the nucleus (5’ cap and 3’ poly-A tail)
eukaryotes
249
Modifications increase translation
efficiency and lifespan of the mRNA
eukaryotic translation
250
Translation takes place on ___
located in the rough endoplasmic
reticulum (translation is physically
separated from transcription)
translation
251
Influence on ___ ___forms the basis of
function in many antibiotics.
gene expression
252
The purpose is to impair function in the
prokaryote without disrupting function in
eukaryotes.
antibiotic
253
Influence on gene expression forms the basis of
function in many __.
antibiotics
254
So what is the Central Dogma?
The flow from DNA to RNA to Protein
