) Conjugation, transformation, and transduction are all ways that bacteria
increase their genetic diversity.
The figure below shows a normal cell transduction pathway. If the receptor wasn't there, which of the following is the most likely outcome?
Cell division will be increased.
The feature of "sticky ends" that makes them especially useful in DNA recombination is their ability to
form hydrogen-bonded base pairs with complementary single-stranded stretches of DNA.
The restriction enzyme BamHI recognizes the DNA sequence GGATCC and always cuts between the two G nucleotides. How many bases long is the sticky end of a DNA molecule that has been cut with BamHI?
four
In order to match the pilot's remains to the correct family using DNA profiling,
each of the 13 STR bands must match.
Restriction enzymes
cut dna at specific sites
The enzyme that converts information stored in RNA to information stored in DNA is
reverse transcriptase.
The bands in the ladder are in 10-base increments, starting with 10 bases at the bottom and going to 70 bases at the top.
Approximately how many bases are in the DNA molecule that the arrow is pointing to?
36 bases
Segments of eukaryotic DNA that can move or be copied from one site to another in the genome are called
transposable elements.
What is the smallest number of cells needed to perform a successful DNA profile?
20
You are trying to produce a cDNA library starting from mRNA in skeletal muscle cells. You add the following components to a tube and let the reaction proceed: skeletal muscle mRNA, free nucleotides, and DNA polymerase. After inspecting the products of the reaction, you do not find any cDNA molecules at all. What is the most likely explanation for this result?
You used DNA polymerase instead of reverse transcriptase.
Based on analysis of the STR sites shown, does the missing pilot belong to any of these three families?
Yes, family 3 matches.
Which step in the creation of cDNA involves the use of reverse transcriptase?
step 3
How many separate molecules of DNA would you end up with if you treated the above DNA molecule with SacI?
four
Below is a figure depicting the whole-genome shotgun method. Which step is most similar to a step used when preparing a genomic library?
step 1
After DNA fragments with matching sticky ends are temporarily joined by complementary base pairing, the union can be made permanent by the "pasting" enzyme
DNA ligase.
Some restriction enzymes do not leave sticky ends when cutting DNA molecules; rather, they cut a restriction site down the middle and leave "blunt-ended" DNA molecules, which do not have any single-stranded nucleotide extensions. Which of the following is not a likely outcome when trying to insert a gene into a plasmid when have both been cut with the same "blunt-ended" restriction enzyme
The gene might be inserted into the plasmid by forming hydrogen bonds.
The production of multiple identical copies of gene-sized pieces of DNA defines 1
gene cloning.
If you wanted to produce a recombinant form of DNase I, what cell type should you use?
mammalian
"Sticky ends" are
DNA fragments with single-stranded ends.
Based on analysis of the STR sites shown, which family is the missing pilot least likely to belong to?
Family 1 and family 2 are equally unlikely.
22) When cloning a gene, one of the steps is to use restriction enzymes to insert the gene of interest into a vector. If you separated the empty vector (the vector without the gene of interest) and the cloned vector (the vector that has the gene of interest added) using agarose gel electrophoresis, what do you expect to observe on the agarose gel if both vectors are loaded at the same position at the top of the gel?
The empty vector would migrate farther down than the cloned vector.
Which of the following processes occurs when a salamander regenerates a lost limb?
Certain cells in the limb dedifferentiate, divide, and then redifferentiate to form a new limb.
There is a mutation in the operator of the trp operon in a cell such that the trp repressor is unable to bind to the operator. If tryptophan is added to the cell, what will happen?
Tryptophan will bind to the repressor, and trp enzymes will be produced.
The development of colon cancer occurs slowly, and colon cancer is more frequently seen in the elderly than the young. This is most likely because
usually six
There is a mutation in a promoter next to a gene such that RNA polymerase can never bind. What steps must occur for the gene to be transcribed?
The DNA must physically bend so that the activator is close to the promoter.
A single cell, the zygote, can develop into an entirely new organism with many different specialized cells. Which of the following statements about this process is false?
Additional genetic information for the formation of specialized cells is passed on to the developing embryo via the mother.
.
A scientist hypothesizes that a new drug turns on a certain gene in a skin cell. Which of the following experiments would be the best to test her hypothesis?
Use qPCR to measure the initial levels of gene expression in skin cells, treat skin cells with the drug and measure the levels of gene expression, and then compare the two measurements.
In female mammals, the inactive X chromosome in each cell
becomes a Barr body.
) A cell has a mutation in both alleles of its p53 gene that causes the p53 protein to be three times as effective as normal. What do you predict would happen to this cell?
The cell would divide normally or possibly not at all.
All of the trees in an orchard were derived from the same rootstock, but half had scion "A" grafted and the other half had a different scion, scion "B," grafted. The trees that were grafted with scion "A" developed large fruits. What characteristics do you think the fruit from the trees that were grafted with scion "B" will have and why?
There is not enough information to know what the fruit will look like
Which of the following statements regarding DNA packing is false
DNA packing tends to promote gene expression.
Which of the following statements about microarrays is false?
Microarrays use tiny portions of double-stranded RNA fragments from a large number of genes.
Which structure in this figure shows one complete nucleosome?
structure D
There is a mutation in the operator of the trp operon in a cell such that the trp repressor is unable to bind to the operator. If tryptophan is added to the cell, what will happen?
Tryptophan will bind to the repressor, and trp enzymes will be produced.
A gene that can cause cancer when present in a single copy in a cell is called a/an
oncogene.
There is a mutation in the operator of the lac operon in a cell such that the lac repressor always stays bound to the operator. If lactose is added to the cell, what will happen?
Lactose will bind to the repressor, and lac enzymes will not be produced.
In thinking about their role in cell division, oncogenes are like the ________ of a car, while tumor suppressor genes are like the ________ of a car.
gas pedal; brakes
Which of the following statements regarding skin cells and muscle cells in your body is true?
Skin cells and muscle cells each contain information about both muscle proteins and skin color.
In multicellular organisms, the coordination of cellular activities relies on
cell-to-cell signaling and signal transduction pathways.
Which of the following molecules are not required to express a gene in eukaryotic cells?
repressor protein
A friend accidentally sends an email to you that contains a computer virus from his computer. Without knowing it, you infect your computer with the virus when you open the email. This process of spreading the computer virus via email is most like which of the following processes?
transduction
) One type of virus that infects bacteria is called a
phage.
Which of the following statements is false?
The start codon can be different depending on what kind of protein is to be translated.
Imagine that a pharmaceutical company was successful at producing a drug based on the CCR5 gene product that is effective at preventing the contraction of AIDS. However, shortly after the drug has been in use, patients and doctors report that the drug is not as effective as it once was. What is the most likely explanation for this result?
Some HIV viruses have genetic variations in the RNA genome that provide resistance to the actions of the drug.
The shape of a DNA molecule is most like
a twisted rope ladder.
Which of the following enzymes catalyzes the production of a strand of RNA from DNA?
RNA polymerase
What is the transcription product of the sequence GCTAGCGATGAC?
CGAUCGCUACUG
If both of these sequences code for proteins, how might the function of protein 2 differ from the function of protein 1?
Protein 1 and protein 2 will function exactly the same.
Which of the following takes place during translation?
the conversion of genetic information from the language of nucleic acids to the language of proteins
Which of the following occurs when RNA polymerase attaches to the promoter DNA?
initiation of a new RNA molecule
A protein coat enclosing a viral genome is known as a/an
capsid.
The way that genetic material of a bacteriophage enters a bacterium is most like the way that
a drug is injected with a hypodermic needle.
The copying mechanism of DNA is most like
taking a picture of yourself and of your reflection in a mirror.
In the genetic code,
many amino acids are specified by more than one codon.
When a T2 bacteriophage infects an Escherichia coli cell, which part of the phage enters the bacterial cytoplasm?
only the DNA
Consider the following sentence: "The dog did not eat." Which of the following variations of this sentence is most like a base substitution mutation?
The doe did not eat.
Which of the following statements regarding viral diseases is false?
Very few new human diseases have originated in other animals because the genetic differences are too great.
Which of the following options most accurately lists the sequence of events in translation?
codon recognition → peptide bond formation → translocation → termination
We would expect that a 15-nucleotide sequence that includes a stop codon at the end (as part of the 15-nucleotide sequence) will direct the production of a polypeptide that consists of
four amino acids.