5 Written Questions
5 Matching Questions
- Expression of a cloned eukaryotic gene in a bacterial cell involves many challenges. The use of mRNA and reverse transcriptase is part of a strategy to solve the problem of
A) post-translational processing.
B) restriction fragment ligation.
C) nucleic acid hybridization.
D) post-transcriptional processing.
- In positive control of several sugar-metabolism-related operons, the catabolite activator protein (CAP) binds to DNA to stimulate transcription. What causes an increase in CAP?
A) increase in glucose and increase in cAMP
B) increase in glucose and decrease in cAMP
C) decrease in glucose and increase in cAMP
D) decrease in glucose and increase in repressor
E) decrease in glucose and decrease in repressor
- DNA microarrays have made a huge impact on genomic studies because they
A) dramatically enhance the efficiency of restriction enzymes.
B) can be used to eliminate the function of any gene in the genome. C) allow the expression of many or even all of the genes in the genome to be compared at
D) allow physical maps of the genome to be assembled in a very short time.
E) can be used to introduce entire genomes into bacterial cells.
- Genetically engineered plants
A) are banned throughout the world.
B) are more difficult to engineer than animals.
C) include a transgenic rice plant that can help prevent vitamin A deficiency.
D) are being rapidly developed, but traditional plant breeding programs are still the only method used to develop new plants.
E) are able to fix nitrogen themselves.
- A researcher needs to clone a sequence of part of a eukaryotic genome in order to express the sequence and to modify the polypeptide product. She would be able to satisfy these requirements by using which of the following vectors?
A) a human chromosome
B) a bacterial plasmid
C) a YAC with appropriate cellular enzymes
D) BAC to accommodate the size of the sequence
E) a modified bacteriophage
- a C) a YAC with appropriate cellular enzymes
- b C) decrease in glucose and increase in cAMP
- c D) post-transcriptional processing
- d C) include a transgenic rice plant that can help prevent vitamin A deficiency
- e C) allow the expression of many or even all of the genes in the genome to be compared at once
5 Multiple Choice Questions
- E) a large number of phages are released at a time
- C) can encode proteins that promote DNA repair or cell-cell adhesion
- A) differentiated cells retain all the genes of the zygote
- B) the amino acid acts as a corepressor
- D) IV only
5 True/False Questions
A eukaryotic gene has "sticky ends" produced by the restriction endonucleaseEcoRI. The gene is added to a mixture containingEcoRI and a bacterial plasmid that carries two genes conferring resistance to ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original. Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline, and nutrient broth without antibiotics.
Bacteria containing a plasmid into which the eukaryotic gene has integrated would grow in
A) the ampicillin broth and the nutrient broth.
B) the nutrient broth only.
C) the nutrient broth, the ampicillin broth, and the tetracycline broth.
D) the nutrient broth and the tetracycline broth only.
E) all four types of broth. → B) continuous transcripton of the structural gene controlled by that regulator
The herpes viruses are very important enveloped DNA viruses that cause disease in all vertebrate species and in some invertebrates such as oysters. Some of the human ones are herpes simplex (HSV) I and II, causing facial and genital lesions, and the varicella-zoster (VSV), causing chicken pox and shingles. Each of these three actively infect nervous tissue. Primary infections are fairly mild, but the virus is not then cleared from the host; rather, viral genomes are maintained in cells in a latent phase. The virus can then reactivate, replicate again, and be infectious to others.
If scientists are trying to use what they know about HSV to devise a means of protecting other people from being infected, which of the following would have the best chance of lowering the number of new cases of infection?
A) medication that destroys surface HSV before it gets to neurons
B) interference with new viral replication in preexisting cases
C) vaccination of all persons with preexisting cases
D) education about avoiding sources of infection
E) treatment of the HSV lesions to shorten the breakout → E) This can help them to decide whether and what kind of chemotherapy is warranted
Which of the following represents a difference between viruses and viroids?
A) Viruses have capsids composed of protein, whereas viroids have no capsids.
B) Viruses cannot pass through plasmodesmata, whereas viroids can.
C) Viruses contain introns, whereas viroids have only exons.
D) Viruses infect many types of cells, whereas viroids infect only prokaryotic cells.
E) Viruses always have genomes composed of DNA, whereas viroids always have genomes composed of RNA. → E) it is an activator for other genes
DNA fragments from a gel are transferred to a nitrocellulose paper during the procedure called Southern blotting. What is the purpose of transferring the DNA from a gel to a nitrocellulose paper?
A) to attach the DNA fragments to a permanent substrate
B) to prepare the DNA for digestion with restriction enzymes
C) to separate the two complementary DNA strands
D) to separate out the PCRs
E) to transfer only the DNA that is of interest → A) to attach the DNA fragments to a permanent substrate
In 1997, Dolly the sheep was cloned. Which of the following processes was used?
A) fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a
B) replication and dedifferentiation of adult stem cells from sheep bone marrow
C) separation of an early stage sheep blastula into separate cells, one of which was incubated in a surrogate ewe
D) isolation of stem cells from a lamb embryo and production of a zygote equivalent
E) use of mitochondrial DNA from adult female cells of another ewe → A) fusion of an adult cell's nucleus with an enucleated sheep egg, followed by incubation in a surrogate