Chapter 7 pt 1
higher amounts of protein
In general, higher levels of transcription lead to ______________________. higher amounts of stem loops. higher amounts of DNA. lower amounts of DNA. lower amounts of protein. higher amounts of protein.
mutagen
A chemical that can increase the rate of mutations is called a _______________________. carcinogen. insertion. mutagen. deletion.
nonsense mutation.
A mutation that results in the presence of a stop codon in the middle of the genetic code is a _____________. missense mutation. frameshift mutation. nonsense mutation. silent mutation.
at the operator region
According to the animation, where does the activation and repression of an operon occur? at the promoter region at the operator region at the structural genes all of the above none of the above
20
According to the chart, how many amino acids are coded for by codons? 64 20 3
when it is bound to its correct tRNA.
An amino acid is considered charged ____________. when it leaves the E site. when it is bound to its correct tRNA. when it binds to the mRNA. when it enters the P site.
histidine
CAU codes for ___________________. isoleucine. tryptophan. proline. serine. histidine.
light-repair mechanism
Enzymes known as photolyases are involved in which type of repair? light-repair mechanism excision-repair mechanism mismatch-repair mechanism all of the above none of the above
frameshift mutations via insertion or deletion of nucleotides.
Ethidium bromide can result in _________________. chromosomal breaks. base mismatching during DNA replication. frameshift mutations via insertion or deletion of nucleotides. thymine dimers.
The original strand will likely have a methyl group attached, while the newly mutated strand will not.
How can a mismatch repair enzyme detect which strand contains the correct DNA sequence? Mismatch repair enzymes look for a bulge in the DNA caused by the mutation. The mutated sequences are easily detected in the presence of light. The mutated sequence has dimers occurring between adjacent bases. The original strand will likely have a methyl group attached, while the newly mutated strand will not.
Protein-dependent termination involves the use of a protein to end transcription.
How does protein-dependent termination differ from protein-independent termination? Protein-dependent termination does not produce RNA. Protein-dependent termination does not dislodge the RNA polymerase from the DNA. Protein-dependent termination involves the use of a protein to end transcription. Protein-dependent termination uses a promoter to end transcription.
Protein-dependent termination involves the use of a protein to end transcription
How does protein-dependent termination differ from protein-independent termination? Protein-dependent termination uses a promoter to end transcription. Protein-dependent termination does not dislodge the RNA polymerase from the DNA. Protein-dependent termination does not produce RNA. Protein-dependent termination involves the use of a protein to end transcription.
It hydrogen-bonds the nucleotide to the parental strand, pairing adenines to thymines and guanines to cytosines.
How does the DNA polymerase know which nucleotide triphosphate to add to the growing strand? It does not; it is a random process that results in genetic diversity for the offspring. It hydrogen-bonds the nucleotide to the parental strand, pairing adenines to thymines and guanines to cytosines. It hydrogen-bonds the nucleotide to the RNA primer made by primase, pairing adenines to thymines and guanines to cytosines. It hydrogen-bonds the nucleotide to the parental strand, pairing adenines to cytosines and guanines to thymines.
one error for every 1,000,000,000 nucleotides copied
How frequently does an error occur in DNA replication in the absence of a mutagen? one error for every 100,000 nucleotides copied one error for every 10,000,000 nucleotides copied one error for every 1,000,000 nucleotides copied one error for every 10,000 nucleotides copied one error for every 1,000,000,000 nucleotides copied
3
How many codons code for the termination of transcription? 64 3 1 61
2, 1, 4, 3
Place the following events of lagging strand DNA synthesis in order: DNA polymerase synthesizes new DNA strand in the 5' to 3' direction. Primase adds an RNA primer. Okazaki fragments are joined together. RNAse removes the RNA primer.
bind to the A site AND are coded by stop codons
Release factors _________________________. are coded by stop codons. bind to the A site. keep the ribosomal subunits together. bind to the A site AND are coded by stop codons. bind to the A site AND keep the ribosomal subunits together. none of the above
5' to 3'
Ribosomes move along the mRNA in which direction? either 5' to 3' or 3' to 5' 5' to 3' 3' to 5'
the process of making protein from RNA.
Translation is _________________________. the process of making RNA from DNA. the process of making protein from RNA. the process of making protein from DNA. the process of making DNA from RNA.
all of the above
Which of the following is involved in translation? ribosomes mRNA amino acids all of the above none of the above
mRNA
Which of the following is not a part of the initiation complex? small ribosomal subunit tRNA charged with Gly mRNA tRNA charged with Met large ribosomal subunit
mRNA
Which of the following is the copy of a DNA sequence used to make protein? rRNA tRNA mRNA
rRNA
Which of the following is used to make ribosomes? mRNA tRNA rRNA
light-repair mechanism
Which of the following repair mechanism(s) does not involve the removal of nucleotides? light-repair mechanism excision-repair mechanism mismatch-repair mechanism all of the above none of the above
light-repair mechanism AND excision-repair mechanism
Which of the following repair mechanisms might be involved in repairing a mutation that results from exposure to UV light? light-repair mechanism excision-repair mechanism mismatch-repair mechanism light-repair mechanism AND excision-repair mechanism all of the above
The leading strand of DNA replication requires only one RNA primer. The lagging strand of DNA replication requires multiple RNA primers
Which of the following statements concerning DNA replication is true? The leading strand of DNA replication requires only one RNA primer. The lagging strand of DNA replication requires multiple RNA primers. The lagging strand of DNA replication requires only one RNA primer. The leading strand of DNA replication does not require an RNA primer.
They are typically 1000 nucleotides in length They are found on the lagging strand of DNA replication.
Which of the following statements regarding Okazaki fragments are true? They are typically 1000 nucleotides in length. They are composed of RNA. They are found on the leading strand of DNA replication. They are found on the lagging strand of DNA replication.
All of the above statements are true.
Which of the following statements regarding RNA polymerase is true? RNA polymerase reads the template strand of DNA. RNA polymerase adds nucleotides to the 3' end of the growing RNA molecule. RNA polymerase binds to the promoter region of the gene prior to starting RNA synthesis. All of the above statements are true. None of the above statements are true
All of the above statements are true
Which of the following statements regarding RNA polymerase is true? RNA polymerase reads the template strand of DNA. RNA polymerase adds nucleotides to the 3' end of the growing RNA molecule. RNA polymerase binds to the promoter region of the gene prior to starting RNA synthesis. All of the above statements are true. None of the above statements are true
All of the above statements are true.
Which of the following statements regarding operons is true? Inducible operons are transcribed only when they are activated. Repressible operons are always transcribed unless they are deactivated by a repressor. The structural genes of an operon typically have the same biochemical function in the cell. All of the above statements are true. None of the above statements are true.
excision-repair mechanism AND mismatch-repair mechanism
Which of the repair mechanism(s) requires assistance from DNA polymerase to make the correction? light-repair mechanism excision-repair mechanism mismatch-repair mechanism excision-repair mechanism AND mismatch-repair mechanism none of the above
It provides a 3' end of the newly synthesized strand, allowing DNA polymerase to begin copying DNA
Why is primase essential for DNA replication? It removes the RNA left from the DNA replication process. It provides a 3' end of the newly synthesized strand, allowing DNA polymerase to begin copying DNA. It provides the RNA that is an essential part of the newly copied chromosome. It repairs the gaps between DNA fragments during lagging strand synthesis.
ionizing radiation
X-rays would be considered which type of mutagen? ionizing radiation nucleoside analog nucleotide-altering chemical nonionizing radiation
tRNA
Which of the following is involved in bringing amino acids to the ribosomes? rRNA mRNA tRNA
methionine
AUG codes for _________________. methionine. stop codon. both of the above.
silent, nonsense, and missense
Base pair substitutions can result in what type(s) of mutation? frameshift mutation missense mutation silent mutation silent, frameshift, and missense silent, nonsense, and missense nonesense mutation
From 5' to 3' on both the leading and lagging strands.
DNA synthesis occurs in which direction? From 5' to 3' on the leading strand and 3' to 5' on the lagging strand. From 5' to 3' on the lagging strand and 3' to 5' on the leading strand. From 3' to 5' on both the leading and lagging strands. From 5' to 3' on both the leading and lagging strands
5-bromouracil
Which of the following is an example of a nucleoside analog? benzopyrene ethidium bromide nitrous acid 5-bromouracil arcidine orange
tRNA.
The anticodon sequence is found on the __________. ribosome. tRNA. DNA. mRNA. amino acid.
DNA replication.
The process of copying DNA prior to cell replication is known as _____________. RNA replication. DNA translation. DNA synthesis. DNA transcription. DNA replication.
is the point where DNA helicase is "unzipping" the double-stranded DNA molecule.
The replication fork __________________. iIs the point where stabilizing proteins bind the single strands of DNA. is the point where DNA helicase is "unzipping" the double-stranded DNA molecule. is what results if the DNA strands begin to degrade. is another term for DNA replication.
ahead of the newly synthesized DNA.
The replication fork moves ___________. ahead of the newly synthesized DNA. away from the direction of newly synthesized DNA. opposite the direction of the DNA helicase. toward the stabilizing proteins.
to copy the information stored in DNA into RNA.
The role of transcription is ___________________. to copy DNA prior to cell division. to copy the information stored in DNA into RNA. to assemble amino acids into proteins. to pass genetic information from one cell to another.
silent mutation
Which mutation is the least likely to be harmful to a cell? nonsense mutation frameshift mutation missense mutation silent mutation
all of the above
Which of the following are genetic elements found in an operon? operator region structural genes promoter all of the above
all of the above
Which of the following codes for leucine? CUU CUG UUA all of the above none of the above
all of the above
Which of the following is a product of transcription? mRNA rRNA tRNA all of the above none of the above
Ions and free radicals resulting from ionizing radiation can break chromosomes.
What is a potential source of mutations from ionizing radiation? Ions and free radicals resulting from ionizing radiation can break chromosomes. Ionizing radiation can result in the formation of thymine dimers. Ionizing radiation can result in nucleoside analogues mispairing with the normal DNA sequence. Ionizing radiation can cause the addition or removal of bases, resulting in a mutation.
The new copies of DNA contain one original strand of DNA and one new strand of DNA.
What is meant by semiconservative replication? The newly made DNA strand is made entirely of new DNA, while the parental DNA is conserved. The new copies of DNA contain one original strand of DNA and one new strand of DNA. Both the new DNA and the parental DNA remain connected during DNA replication. Both the new DNA molecules are made up of new DNA.
They hold the separated strands apart and prevent their degredation.
What is the function of stabilizing proteins? They synthesize new strands of DNA. They form the replication fork. They use ATP to break the hydrogen bonds between the strands of DNA. They hold the separated strands apart and prevent their degredat
They link the leading strand DNA polymerase and the lagging strand DNA polymerase together.
What is the function of the connector proteins? They produce the Okazaki fragments. They link the leading strand DNA polymerase and the lagging strand DNA polymerase together. They enable one parental DNA strand and one newly synthesized DNA strand to be held together. They allow DNA synthesis to occur from the 3' to 5' direction.
A site, P site, E site
What is the order of ribosomal sites that a charged tRNA molecule passes through? A site, P site, E site P site, A site, E site A site, E site, P site E site, P site, A site E site, A site, P site
DNA helicase uses the energy from ATP to break the hydrogen bonds between two DNA strands, thereby "unzipping" the molecule.
What is the role of DNA helicase in DNA replication? DNA helicase stabilizes the single strands of DNA during replication. DNA helicase synthesizes new strands of DNA. DNA uses DNA to get energy from ATP. DNA helicase uses the energy from ATP to break the hydrogen bonds between two DNA strands, thereby "unzipping" the molecule.
The newly made chromosome would consist of DNA and RNA molecules
What might happen if the cell does not have RNAse? The hydrogen bonding between the DNA strands would all be broken. There would be gaps of missing DNA throughout the newly synthesized DNA. The newly made chromosome would consist of DNA and RNA molecules. DNA polymerase would not have a 3' to begin DNA synthesis
The parent must copy its own DNA and provide a copy to its offspring.
What must occur for an organism to pass its genetic information on to its offspring? The parent must copy its own DNA and provide a copy to its offspring. The parental chromosome must be given to the offspring. The host chromosome must be degraded. A novel DNA chromosome must be made by the parent cell and given to its offspring.
each of the original DNA strands
What serves as the template for DNA replication? proteins that are associated with DNA replication the new DNA strands RNA from the cell each of the original DNA strands
frameshift mutation
What type of mutation can change all subsequent amino acids following it? missense mutation nonsense mutation frameshift mutation silent mutation
DNA polymerase
Which enzyme(s) can synthesize new strands of DNA? primase DNA polymerase ligase #1 and #2 all of the above
higher amounts of protein.
n general, higher levels of transcription lead to ______________________. lower amounts of protein. higher amounts of protein. higher amounts of DNA. lower amounts of DNA. higher amounts of stem loops.