5 Written questions
5 Matching questions
- Pharmacogenetics is an increasingly important discipline that uses genetic information to tailor the prescription of drug treatments to individuals. In the case of chemotherapy for breast cancer, for example, different patients need and/or respond to different treatments.
Breast tumor biopsy specimens can be typed for a number of gene expression patterns. Together, these can provide risk analysis for the likely aggressive growth and metastasis of the tumor. How can this most help the physician and patient?
A) This can help them decide whether the tumor should be removed.
B) Some patients want to know as much as possible.
C) This can help to aggregate health statistics.
D) Some physicians may use the information to decide what to do, but not tell the patient.
E) This can help them to decide whether and what kind of chemotherapy is warranted.
- One successful form of gene therapy has involved delivery of an allele for the enzyme adenosine deaminase (ADA) to bone marrow cells of a child with SCID, and delivery of these engineered cells back to the bone marrow of the affected child. What is one major reason for the success of this procedure as opposed to many other efforts at gene therapy?
A) The engineered bone marrow cells from this patient can be used for any other SCID patient.
B) No vector is required to introduce the allele into ADA-negative cells.
C) The engineered cells, when reintroduced into the patient, find their way back to the bone
D) The ADA-introduced allele causes all other ADA-negative cells to die.
E) The immune system fails to recognize cells with the variant gene.
- Transcription factors in eukaryotes usually have DNA binding domains as well as other domains that are also specific for binding. In general, which of the following would you expect many of them to be able to bind?
B) protein-based hormones
D) other transcription factors
- Antiviral drugs that have become useful are usually associated with which of the following properties?
A) removal of viral proteins
B) interference with viral replication
C) prevention of the host from becoming infected
D) removal of viral mRNAs
E) ability to remove all viruses from the infected host
- A group of six students has taken samples of their own cheek cells, purified the DNA, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest.
Analysis of the data obtained shows that two students each have two fragments, two students each have three fragments, and two students each have one only. What does this demonstrate?
A) Each pair of students has a different gene for this function.
B) Each of these students is heterozygous for this gene.
C) The students with three fragments are said to have "fragile sites."
D) The two students who have two fragments have two restriction sites within this gene.
E) The two students who have two fragments have one restriction site in this region.
- a C) The engineered cells, when reintroduced into the patient, find their way back to the bone marrow
- b D) other transcription factors
- c B) interference with viral replication
- d E) This can help them to decide whether and what kind of chemotherapy is warranted
- e E) the two students who have two fragments have one restriction site
5 Multiple choice questions
- C) Viral genomes are usually similar to the genome of the host cell
- B) methylation of the DNA is maintained because methylation enzymes act at DNA sites where one strand is already methylated and thus correctly methylates daughter strands after replication
- B) ~6
- B) the newly emerging virus will die out rather quickly or will mutate to be far less lethal
- C) ~6,300
5 True/False questions
RNA viruses require their own supply of certain enzymes because A) these enzymes translate viral mRNA into proteins.
B) host cells rapidly destroy the viruses.
C) these enzymes cannot be made in host cells.
D) host cells lack enzymes that can replicate the viral genome.
E) these enzymes penetrate host cell membranes. → D) host cells lack enzymes that can replicate the viral genome
If you were to observe the activity of methylated DNA, you would expect it to
A) have turned off or slowed down the process of transcription.
B) induce protein synthesis by not allowing repressors to bind to it.
C) be unwinding in preparation for protein synthesis.
D) be very actively transcribed and translated.
E) be replicating nearly continuously. → C) increased concentrations of sugars such as arabinose in the cell
You isolate an infectious substance that is capable of causing disease in plants, but you do not know whether the infectious agent is a bacterium, virus, viroid, or prion. You have four methods at your disposal that you can use to analyze the substance in order to determine the nature of the infectious agent.
I. treating the substance with nucleases that destroy all nucleic acids and then determining whether it is still infectious
II. filtering the substance to remove all elements smaller than what can be easily seen under a light microscope
III. culturing the substance by itself on nutritive medium, away from any plant cells
IV.treating the sample with proteases that digest all proteins and then determining whether it is still infectious
Which treatment would you use to determine if the agent is a prion? A) I only
B) II only
C) III only
D) IV only
E) either I or IV → D) IV only
A researcher found a method she could use to manipulate and quantify phosphorylation and methylation in embryonic cells in culture. She tried decreasing the amount of methylation enzymes in the embryonic stem cells and then allowed the cells to further differentiate. Which of the following results would she most likely see?
A) increased chromatin condensation
B) decreased chromatin condensation
C) inactivation of the selected genes D) decreased binding of transcription factors
E) abnormalities of mouse embryos → E) abnormalities of mouse embryos
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.
In electron micrographs of HSV infection, it can be seen that the intact virus initially reacts with cell surface proteoglycans, then with specific receptors. This is later followed by viral capsids docking with nuclear pores. Afterward, the capsids go from being full to being "empty." Which
of following best fits these observations?
A) Only the genetic material of the virus is involved in the cell's infectivity, and is injected like the genome of a phage.
B) The viral envelope is not required for infectivity, since the envelope does not enter the nucleus.
C) The viral envelope mediates entry into the cell, the capsid entry into the nuclear membrane, and the genome is all that enters the nucleus.
D) Viral capsids are needed for the cell to become infected; only the capsids enter the nucleus.
E) The viral capsid mediates entry into the cell, and only the genomic DNA enters the nucleus, where it may or may not replicate. → D) host cells lack enzymes that can replicate the viral genome