HW 13: Bio-Tech

Gel looks blank

- Forgot DNA dye. - Forgot to connect the power source. - Forgot to add DNA.

Forgot to add DNA.

- Forgot to add restriction enzymes to your DNA. - The restriction enzyme you select does not have a restriction site in your DNA.

Which of the following conditions/substances are currently the most common for plants to have been genetically modified to resist? (Select all that apply)

- Herbicides - Insect herbivory

Cellular DNA Replication (1/2)

- Occurs in the nucleus - Uses helicase - Involves Okazaki fragments - Produces a lagging strand

Polymerase Chain Reaction (2/2)

- Occurs outside the nucleus - Uses TAQ polymerase - Requires denaturation - Requires heat cycles

Which of the following are uses for cDNA? (Select all that apply)

- Studying gene expression at different developmental stages - Expressing genes for commercial use - Inferring sequences of proteins expressed in a specific tissue

DNA fingerprinting would be a useful technique for _____. (Select all that apply)

- identifying remains following natural disasters - distinguishing between potential suspects in a crime - reuniting families separated by an earthquake

Arrange the following events in the proper sequence for gene cloning. 1 = Incorporate gene into bacterial plasmid. 2 = Isolate DNA from organism containing desired gene. 3 = Incorporate cloned gene into bacterial cells. 4 = Fragment DNA with restriction enzyme.

2, 4, 1, 3

Arrange the following in the proper sequence in which they occur during a single PCR cycle. 1. Addition of DNA nucleotides by Taq polymerase 2. Complementary base pairing between primers and target DNA 3. Heat separation of strands of target DNA

3, 2, 1

If you visit 10 random soybean farms in the United States, on about how many of them will you find a transgenic crop?

9

During PCR, which primer anneals to DNA with its 3' end toward the center of the sequence to be amplified?

Both the forward and reverse primers

A farmer is growing transgenic Bt maize. What are you unlikely to see in those fields?

Caterpillars

PCR requires all of the following EXCEPT

DNA ligase.

Since all of the resulting colonies are identical, the desired gene can then be isolated from each colony.

False

Select if the following statement is True or False and the reason for your choice: Genome editing is a powerful new tool, but unfortunately it can only be used to inactivate a gene.

False, because added DNA can promote replacement by homology-directed repair.

DNA fragments would look normal

Forgot to add a molecular weight marker.

What restriction enzyme recognition sequence is NOT palindromic; that is, the last three nucleotides are NOT complementary to the first three nucleotides?

GCTTGC CGAACG

A medical researcher is trying to develop a diagnostic technique for a disease which is characterized by the misexpression of a large number of unrelated genes. What would be the most appropriate technique?

Gene chip

Why do plants infected with Agrobacterium tumefaciens by genetic engineers not form tumors?

Genetic engineers have removed the tumor-causing genes.

Which statement best explains the role of a vector in recombinant DNA technology?

It carries a segment of recombinant DNA.

You are an expert witness in a murder trial. The defendant has a DNA fingerprint identical to that of a sample from the scene of the crime. How strong is this evidence linking the accused to the scene?

Strong, because it is highly unlikely that two people will have the same fingerprint, unless they are closely related.

Why is Taq DNA polymerase used in PCR reactions rather than a 'normal' DNA polymerase?

Taq polymerase is stable at the high temperatures that are used in the PCR reaction.

What feature of DNA makes DNA fingerprinting possible?

The number of repeats in a tandem repeat sequence is highly variable from one individual to another.

How will the researcher know if the gene of interest is in a bacterial colony?

The researcher can probe for the gene of interest using a labeled piece of DNA that is complementary to the gene of interest.

Human DNA cut with restriction enzyme A can be joined to

bacterial DNA cut with restriction enzyme A.

Restriction enzymes do all of the following except

isolate and purify DNA

"Sticky ends" are

single-stranded DNA sequences that are generated by staggered cuts.

Cloned genes are first inserted within the _____ to generate a transgenic plant.

the Ti plasmid