Question 1

Why is the use of RNAi as a means for blocking RNA translation preferred over the use of antisense RNA?

Accepted Answer

RNAi is more stable and effective than antisense RNA because it involves the use of double-stranded RNA, which is more resistant to degradation and can effectively silence gene expression by targeting mRNA for degradation.

Question 2

For which of the following processes would we use homologous recombination?

Accepted Answer

Homologous recombination can be used to inactivate specific genes by introducing mutations or disrupting the reading frame. This is commonly done in genetic engineering to create knockout organisms or study gene function.

Question 3

The use of which of the following allows researchers to examine the patterns of gene expression for a large number of genes simultaneously?

Accepted Answer

DNA microarray technology allows researchers to simultaneously monitor the expression of thousands of genes. It involves attaching short DNA sequences (probes) that are complementary to specific genes onto a surface known as a microarray chip. The labeled RNA sample is hybridized to the microarray chip, and the resulting pattern of labeled spots represents the level of expression for each gene in the sample.

Question 4

Which of the following best describes the major advantage of using microarrays to detect gene expression differences across the genome, as compared with hybridization technologies?

Accepted Answer

The answer of Which of the following best describes the...

Question 5

Variation at a specific gene is known to affect metabolism in mice, but it is not clear which of the nucleotides are responsible for the changes. In addition to recombinant DNA technology, which the following techniques would be most relevant for revealing which of the nucleotides affect metabolism?

Accepted Answer

Mutagenesis is the process of generating random mutations in a gene of interest to determine the functional significance of each nucleotide. This technique could be used to identify which specific nucleotides are responsible for the changes in metabolism observed in the mice. Homologous recombination, antisense RNA, RNAi, and artificial synthesis are all useful techniques, but they do not directly address the question of which nucleotides are responsible for the metabolic changes.

Question 6

Who discovered that a mold makes the antibiotic penicillin?

Accepted Answer

Alexander Fleming discovered that a mold called Penicillium can produce the antibiotic penicillin.

Question 7

Which of the following statements about RNAi technology is false?

Accepted Answer

All the statements provided about RNAi technology are true. RNAi is indeed based on a natural process for inhibiting translation, was discovered in the 1990s, has been used in therapies such as for macular degeneration, and involves double-stranded RNA.

Question 8

Laura van 't Veer and her colleagues discovered specific differences between cancer patients with good prognoses and those with poor prognoses. The technique most closely associated with the diagnostic tool they invented is

Accepted Answer

Laura van 't Veer and her colleagues invented a diagnostic tool based on DNA microarray technology, which allows researchers to analyze the expression levels of thousands of genes simultaneously to identify specific genetic patterns associated with different types of cancer and disease prognosis.

Question 9

Methods developed by the _______ industry were most directly responsible for the development of DNA microarray technologies.

Accepted Answer

The semiconductor industry developed the technology of photolithography, which was later adapted to develop the DNA chip technology used in DNA microarrays.

Question 10

For which of the following techniques is the synthesis of oligonucleotides most directly useful?

Accepted Answer

Oligonucleotides are short sequences of nucleotides (20-25 bases) that can be synthesized to specifically bind to a target DNA sequence. This technique is most directly useful in the polymerase chain reaction (PCR) where specific oligonucleotide primers are used to amplify target DNA.

Question 11

Which of the following necessarily makes use of reverse transcriptase?

Accepted Answer

Construction of a cDNA library involves the conversion of mRNA to cDNA using reverse transcriptase, which makes it the only option that necessarily involves the use of this enzyme. Southern blotting involves the use of probes to detect DNA fragments, gene library construction typically involves the use of restriction enzymes and ligases to create recombinant DNA molecules, gene knockout studies involve targeted mutations of genes, and pharming involves the production of proteins using genetically modified organisms.

Question 12

What does the "c" in "cDNA library" stand for?

Accepted Answer

The "c" in "cDNA library" stands for complementary. This is because the library is generated using reverse transcription to synthesize complementary DNA from RNA templates.

Question 13

Which of the following techniques is most likely to make use of reverse transcriptase?

Accepted Answer

The answer of Which of the following techniques is most...

Question 14

Which of the following statements about mouse embryonic stem cells is true?

Accepted Answer

All of the given statements are true about mouse embryonic stem cells. They can serve as hosts for transfection studies using homologous recombination, they are unspecialized, and they can be used in knockout studies.

Question 15

Oblimerson, a drug developed against cancer, is one example of the uses of _______ technology.

Accepted Answer

Oblimerson is an example of antisense RNA technology, which involves using a strand of nucleic acid that binds to the mRNA of a specific gene to inhibit its expression, often used in cancer treatment.

Question 16

Which of the following would not be considered a form of biotechnology?

Accepted Answer

The synthetic production of nylon does not involve the use of living organisms or genetic manipulation, which are key components of biotechnology.

Question 17

Which of the following statements is true?

Accepted Answer

cDNA libraries are constructed from complementary DNA produced by reverse transcription of mRNA. Therefore, they only contain expressed genes found in the tissue at the time of sampling. A genomic library, on the other hand, contains all DNA sequences in the genome, including non-coding regions and introns. Therefore, choice A is incorrect. Choice C is also incorrect as cDNA only represents expressed genes. Choice D is false as mRNA has a short lifespan in the cytoplasm.

Question 18

Which of the following can be used to inhibit translation of a specific gene?

Accepted Answer

Both antisense RNA and interference RNA can be used to inhibit translation of a specific gene. Antisense RNA is a single-stranded RNA molecule that is complementary to the mRNA transcript of a target gene, and it binds to the mRNA to prevent translation. Interference RNA (also known as siRNA or shRNA) is a double-stranded RNA molecule that is processed by the cell to form short interfering RNAs that bind to the target mRNA and prevent translation. DNA chips are not used to inhibit translation, but rather to measure gene expression levels.

Question 19

Humans have been using biotechnology for _______ years.

Accepted Answer

Humans have been using biotechnology for at least 8,000 years. This can be seen in ancient practices such as fermentation for food and drink, selective breeding of crops and animals, and the use of natural remedies for medical purposes.

Question 20

The use of which of the following would be most appropriate for inhibiting transcription of a specific gene?

Accepted Answer

The answer of The use of which of the following...

Quiz 18: Recombinent Dna and Biotechnology