bio 115- final exam
describe the promoter of prokaryotes during transcription
-35 and -10 boxes, and the promoter is dna
what are three reasons why mutations occur
1) unrepaired mistakes in DNA synthesis during S phase 2) mistakes separating homologs or sister chromatids in meiosis. 3) exposure to DNA damaging chemicals
Codons are made up of ____ nucleotides each
3
How many RNA nucleotides bases specify an amino acid?
3
Put the following events of bacterial transcription in chronological order. 1. Sigma binds to the promoter region. 2. The double helix of DNA is unwound, breaking hydrogen bonds between complementary strands. 3. Sigma binds to RNA polymerase. 4. Sigma is released. 5. Transcription begins.
3. Sigma binds to RNA polymerase. 1. Sigma binds to the promoter region. 2. The double helix of DNA is unwound, breaking hydrogen bonds between complementary strands. 5. Transcription begins. 4. Sigma is released.
Choose the answer that places the following events of protein synthesis in the proper order. 1. An amino-acyl tRNA binds to the A site. 2. A peptide bond forms between the new amino acid and a methionine amino acid. 3. The ribosome moves so that the "empty" tRNA moves from the P site to the E site and the amino-acyl tRNA moves from the A site to the P site. 4. A small ribosomal subunit binds with mRNA, the tRNA for methionine (in the P site), and a large ribosomal subunit 5. tRNA in the E site disassociates from the complex.
4. A small ribosomal subunit binds with mRNA, the tRNA for methionine (in the P site), and a large ribosomal subunit 1. An amino-acyl tRNA binds to the A site. 2. A peptide bond forms between the new amino acid and a methionine amino acid. 3. The ribosome moves so that the "empty" tRNA moves from the P site to the E site and the amino-acyl tRNA moves from the A site to the P site. 5. tRNA in the E site disassociates from the complex.
Place the following steps in the correct order to explain how miRNA works in RNAi. Not all steps are shown. 1. The RISC protein complex binds the miRNA. 2. The newly transcribed RNA forms hairpins. 3. The precursor miRNA is partially processed and exported to the cytoplasm. 4. RNA polymerase transcribes the gene that encodes the precursor miRNA. 5. The RISC/miRNA complex blocks transcription of its target mRNA.
4. RNA polymerase transcribes the gene that encodes the precursor miRNA. 2. The newly transcribed RNA forms hairpins. 3. The precursor miRNA is partially processed and exported to the cytoplasm. 1. The RISC protein complex binds the miRNA. 5. The RISC/miRNA complex blocks transcription of its target mRNA.
Which is the coding strand? (what prime direction)
5'-3'
codons are written in ______'-_____'?
5'-3'
What is primary protein structure?
A sequence of amino acids
Which of the following IS a capability of natural selection?
Allows for the fittest individuals to produce more offspring.
How can one eukaryotic gene lead to the production of multiple different proteins?
Alternative Splicing
All of the following are necessary for natural selection to occur EXCEPT: A. There is differential reproductive success within populations, i.e. some individuals have more offspring than others. B. Characteristics acquired by individuals over the course of their lifetime, i.e. big muscles from weight lifting, are passed on to their offspring. C. Populations have the ability to produce more individuals than the environment can support. D. The fittest individuals leave the most offspring. E. Variation exists in populations (all individuals are NOT the same).
Characteristics acquired by individuals over the course of their lifetime, i.e. big muscles from weight lifting, are passed on to their offspring.
Which strand can we easily use to predict the mRNA sequence?
Coding strand but replace T's with U's
How does the presence of glucose in an E. coli's environment affect the transcription of the lac operon?
Increased glucose levels decrease the level of cAMP, leading to less frequent transcription.
What happens to RNA polymerase in a eukyarotic cell after it has completed transcription of a gene?
It is free to bind to another promoter and begin transcription.
Why does the presence of extinct forms and transitional features in the fossil record support evolution by natural selection?
It supports the hypothesis that species change over time.
The children of athletes tend to be much more athletic, on average, than other children because the physical characterics their parents built up over their lifetimes have been passed on to their children. This statements is more:
Lamarckian
Human arms and bat wings have fairly similar skeletal structure. The corresponding bones in whale fins have very different shapes and proportions. However, genetic data suggests that humans, bats, and whales share a common ancestor. Which of the following is the most likely explanation for these data?
Natural selection in an aquatic environment resulted in significant changes to whale fin anatomy.
Does RNA processing occur in prokaryotes during transcription? If so list the types of processing
No
Fill in the blanks. Transcription is the creation of ______ from a(n) ______ template.
RNA / DNA
Death cap mushrooms contain a toxin called alpha-amanitin, a toxin that inhibits transcription. What would you predict to be the immediate outcome of adding alpha-amanitin to a cell?
Reduced production of one or more types of RNA
describe the promoter of eukaryotes during transcription
TATA box, promoter is dna
Which strand does RNA polymerase use to make RNA?
Template strand
If the lac repressor were altered so it could not release lactose once lactose was bound to it, then you would predict that
The repressor could not bind to DNA.
One frog species in Ecuador produces a toxin which causes paralysis in other animals. However, the production of this toxin costs frogs a great deal of energy. Which statement best explains the presence of this toxin in this frog species?
The toxin producing frogs are able to avoid predation more effectively and produce greater numbers of offspring than non-toxin producing frogs.
A codon sequence within an mRNA molecule has the following sequence: 5'- ACG -3'. What is the sequence of the anticodon of the tRNA that will bind this codon?
UGC
Does RNA processing occur in eukaryotes during transcription? If so list the types of processing
Yes, 5' cap, poly A tail, splice out introns
You want to engineer a bacterium to produce the gene product of a eukaryotic gene. What must you include in addition to the coding exons of the genes?
a bacterial promoter sequence
During translation, peptide chain elongation to produce a single protein continues until _________?
a stop codon in the A-site binds a release factor.
Select all that apply. Imagine you discover a mutation in a eukaryotic gene that leads to loss of function of the protein that it encodes. You determine the mutant gene's nucleotide sequence from start site for transcription to the termination point of transcription and find no differences between the mutant gene and the normal gene. Where on the DNA could the mutation be?
an enhancer a promoter-proximal element
Select all that apply: Which of the following lead to chromatin condensation?
an enzyme adds methyl groups to DNA An enzyme removes acetyl groups on histones
Histone deacetylases are enzymes that remove acetyl groups from histones. You treat cells with a drug that inhibits histone deacetylases. This drug treatment leads to...
an increase in gene expression
pro or eu: Translation occurs in the cytoplasm.
both
what give nucleic acids a reading frame?
codons
Which of the following best describes the relationship between a newly synthesized RNA molecule and the DNA template strand?
complementary
where does transcription occur in prokaryotes
cytoplasm
Eukaryotic genomes have gene sequences that can code for more than one polypeptide sequence because _____.
different exons can be cut out of the pre-mRNA
synthesis of mRNA
elongation
The driving force behind natural selection is:
environment
all the chemical tags covering DNA and histones in a cell or organism
epigenome
lipid bond
ester
pro or eu: Transcription occurs in the nucleus.
eukaryotic
True or False? If both glucose and lactose are found in the environment of a E. coli cell, lactose only will be used in the bacterium's metabolism.
false
the addition or deletion of nucleotides in any number other than multiples of 3
frameshift mutation
The [ ] is/are arranged sequentially after the promoter.
genes of an operon
all of the genetic information in the DNA of a cell or organism
genome
transcription and translation link ________ to __________
genotype, phenotype
carbohydrate bond
glycosidic
operon NOT transcribed, or HIGH/LOW? lactose present and glucose absent
high rate
A(n) [ ] is a specific small molecule that binds to a bacterial repressor protein and changes its shape so that it cannot bind to an operator, thus switching an operon on.
inducer
begins transcription in a specific place and direction on the DNA template strand
initiation
During RNA processing a(n) ___________ is added to the 3' end of the RNA.
long string of adenine nucleotides
operon NOT transcribed, or HIGH/LOW? lactose and glucose present
low rate
Codes for a protein.
mRNA
In eukaryotic cells, RNA processing converts the RNA transcript into ______.
mRNA
messenger rna
mRNA
If homologs fail to separate in meiosis I, then the resulting daughter cells have too _____ or too _____ chromosomes.
many, few
a change in nucleotide sequence that changes the amino acid specified by a codon
missense mutation
Mistakes in meiosis that lead to abnormal chromosome numbers
nondisjunction
a change in nucleotide sequence that results in an early stop codon
nonsense mutation
operon NOT transcribed, or HIGH/LOW? lactose absent
not transcribed
where does transcription occur in eukaryotes
nucleus
Chromosomal mutations either change the _______ or ________ of chromosomes
number, structure
Regulatory proteins often bind to the [ ] to control expression of the operon.
operator
A(n) [ ] is a stretch of DNA consisting of an operator, a promoter, and genes for a related set of proteins, usually making up an entire metabolic pathway.
operon
protein bond
peptide
RNA polymerase is the enzyme that synthesizes RNA. It catalyzes the formation of _______ bonds.
phosphodiester
nucleic acid bond
phosphodiester
Which of the following levels of control allow for a rapid response?
post translational control
type of control? A protein needs to have a phosphate group added to its structure before it can perform its function.
post-translational
pro or eu: The promoter for a gene contains a -10 and -35 box.
prokaryotic
A(n) [ ] is a specific nucleotide sequence in DNA that binds RNA polymerase, positioning it to start transcribing RNA at the appropriate place.
promoter
What determines the start site and direction of transcription?
promoter
a site in DNA that recruits RNA polymerase
promoter
all the proteins expressed in a cell or an organism
protenome
Along with proteins, makes up a ribosome.
rRNA
A(n) [ ] is a protein that inhibits gene transcription. In bacteria, this protein binds to the DNA in or near the promoter.
repressor
enzyme that makes rna
rna polymerase
The similarity of the limb bone structure of humans, bats, whales, birds and horses is due to them
sharing a common ancestor
What protein(s) associate with the promoter of prokaryotes during transcription?
sigma
a change in nucleotide sequence that does not change the amino acid specified by a codon
silent mutation
Nondisjunction can also occur in meiosis II if _________ ________ fail to separate.
sister chromatids
Is a carrier for amino acids. Harbors an anticodon.
tRNA
ends transcription (mRNA synthesis)
termination
Which of these are required in order for natural selection to occur? (multiple answers can be selected)
that some individuals leave more offspring than others heritable variation
process that makes RNA
transcription
What protein(s) associate with the promoter of eukaryotes during transcription?
transcription factors
type of control? RNA polymerase needs additional proteins to tightly bind a gene's promoter.
transcriptional
all the mRNA molecules expressed in a cell or organism
transcriptome
process that makes proteins
translation
type of control? mRNA is quickly degraded by an enzyme in the cell's cytoplasm before a protein can be made.
translational
True or False? A missense mutation is one where a single nucleotide of DNA differs, leading to the change of a single amino acid.
true
True or False? The lac operon in E. coli utilizes both positive and negative control of gene expression.
true
True or False? Transcription and translation happen almost simultaneously in prokaryotes.
true
The genetic code is... select all that apply
unambiguous redundant universal conservative