Chapter 12A & 12B

Genomics may eventually provide information for treatment of disease __________.

based on the genetic makeup of each patient

Which of these pairs would have exactly the same DNA restriction fragments?

identical twins

A nucleic acid probe is frequently used to __________.

identify genes that have been inserted into bacterial plasmids or genes that have been separated by gel electrophoresis A nucleic acid probe is a short single-stranded probe of either DNA or RNA that is complementary to the sequence of interest. It will base-pair with the sequence of interest in a plasmid or gel, revealing the location of that sequence.

DNA profiling determines __________.

if two samples of DNA are from the same person

This is just one example of _______________, the branch of biology that studies whole _________________, which are the complete sets of DNA found within organisms.

1. Genomics 2. Genomes

Why was Simplot interested in creating a potato that produced less acrylamide?

Acrylamide is a suspected carcinogen.

Gene therapy involves __________.

Adding a functioning version of the defective gene to the cells of an individual. In gene therapy, a new, functional gene is inserted into the somatic cells of the tissue affected by the disorder.

A genetically modified variety of tomato is created and approved for human consumption. Which of the following is most likely to not support this?

Center for Food Safety

Which enzyme "pastes" DNA fragments together?

DNA ligase This enzyme ligates (ties together) DNA fragments.

What is gene cloning?

Gene cloning occurs when a bacterium carrying a recombinant plasmid reproduces, followed by further reproductions, thus making multiple copies of the recombinant plasmid.

In a PCR reaction, the strands of DNA are first separated by ___.

Heating Heat separates the DNA strands.

The ______________________ was a massive scientific undertaking meant to identify and sequence all of the genes found In a human cell.

Human Genome Project

Most of human DNA consists of __________.

Noncoding regions. About 98% of our DNA consists of noncoding regions that may be used for gene control, as introns, repetitive DNA sequences, and other unknown functions.

Which part of a DNA nucleotide contains a negative charge?

Phosphate The phosphate group of a nucleotide, represented here as a yellow ball, contains a negative charge.

One of the interesting conclusions from this project was that only about 1.5% of human DNA encodes for ________________.

Proteins

You are a plant geneticist and wish to alter strawberries using the same technique as was used for the Innate Potato. Which of the following do you use?

RNA interference

DNA used in recombinant DNA techniques is first cut into fragments by __________.

Restriction enzymes. Restriction enzymes cut DNA molecules at specific locations, each of which contains a recognition sequence, or restriction site.

What is the correct sequence of events that occur in a PCR reaction?

Separation of DNA strands; addition of primers; use of DNA polymerase to produce second strand of DNA.

Gel electrophoresis separates pieces of DNA based on _________.

Size

Much of genetic engineering uses plasmids, which are __________.

Small circlets of DNA found in bacteria. A plasmid is a small, circular, self-replicating DNA molecule separate from the bacterial chromosome.

DNA polymerase is a heat-sensitive enzyme. What is one thing that would need to be considered concerning the activity of this enzyme in PCR when the temperature is heated during each cycle to separate the DNA strands?

That the DNA polymerase could be denatured. The DNA polymerase enzyme could be denatured by heat.

The human Y chromosome can be used to provide data about recent human evolution because __________.

The Y chromosome passes essentially intact from father to son. By comparing Y DNA, researchers can learn about the ancestry of human males.

DNA fingerprinting works well as a forensic tool because __________.

Two different samples of DNA can be shown to be from the same individual. For example, a DNA sample from a suspected murderer can be matched to a DNA sample taken from the crime scene.

Putting a human gene into the plasmids of bacteria has enabled scientists to __________.

Use bacteria as "factories" for protein products such as insulin. Clones carrying introduced plasmids can be grown in a liquid culture in large tanks, where they produce large amounts of the introduced gene or even the protein product of that gene.

Archaeologists unearthed a human skull with a small dried fragment of the scalp still attached. They extracted a tiny amount of DNA from the scalp tissue. How could they obtain sufficient DNA for an analysis of the ancient human's genes?

Use the polymerase chain reaction.

When is PCR particularly applicable?

When there are small quantities of DNA to analyze PCR is used to amplify DNA.

You are interested in trying an Innate Potato. Where are you most likely to find one?

Your local grocery store.

Which of the following is an example of a transgenic organism?

a bacterium with human gene for producing insulin

In recombinant methods, the term "vector" refers to __________.

a plasmid or other agent used to transfer foreign genes to a living cell A cloning vector is a DNA molecule that can carry foreign DNA into a cell, where it can replicate.

Which of the following would be considered a transgenic organism?

a rat with rabbit hemoglobin genes. Transgenic organisms contain genes from other species.

An enzyme that "cuts" DNA at a specific sequence of bases is called _____.

a restriction enzyme

What two enzymes are needed to produce recombinant DNA?

a restriction enzyme and a ligase

Which of the following choices best defines "recombinant DNA technology"?

combining genes from different species Recombinant DNA technology involves combining genes from two sources, even different species, into a single chromosome or individual.

DNA profiling, a forensic procedure now being utilized to identify individuals, __________.

compares the DNA banding patterns of small segments of chromosomes A DNA profile is an electrophoretic pattern of DNA bands generated by producing restriction fragments. In forensics, it is used to compare DNA samples from the suspect and victim with those found at the crime scene.

Restriction enzymes __________________________.

cut DNA at specific nucleotide sequences

DNA testing (profiling) has been used to determine the guilt or innocence of crime suspects. This works because __________.

every person has a unique DNA sequence

A nucleic acid probe can be used to __________.

find a particular nucleotide sequence within a large segment of DNA A nucleic acid probe is single-stranded and will bind to a complementary sequence.

Which of the following is likely to contain the most acrylamide?

fried potato

The polymerase chain reaction (PCR) is a useful technique because it can __________.

make a large amount of DNA from a tiny amount

A supplemental appendix is to a book as a ____________ is to a bacterial chromosome.

plasmid

Which technique can copy, or clone, a piece of DNA?

polymerase chain reaction This technique can make millions of copies of a single piece of DNA.

Human insulin is produced in large quantities by __________.

recombinant E. coli bacteria grown in large fermentation vats This recombinant bacterium expresses the human insulin gene.

Gene therapy involves __________.

replacing defective human genes with the correct human gene

Electrophoresis is used to __________.

separate fragments of DNA DNA fragments produced with restriction enzymes are separated from one another on the basis of their size and electrical charge.

When a restriction enzyme cuts a DNA molecule, the cuts are staggered so that the DNA fragments have single-stranded ends. This is important in recombinant DNA work because __________.

the fragments will bond to other fragments with complementary single-stranded ends A result of the action of a restriction enzyme is restriction fragments with single-stranded, sticky ends.

Transgenic organisms can be scientifically or commercially useful only if __________.

the inserted ("foreign") gene is expressed in the host organism Transgenic organisms, containing genes from another species, have been developed for potential agricultural use.

The process of accurately amplifying a sample of DNA is called __________________________.

the polymerase chain reaction

Opponents of genetically modified foods are concerned about a variety of issues, including __________.

the possibility that transgenic plants may cross-pollinate with wild strains, introducing foreign genes

DNA profiles used as evidence in a murder trial look something like supermarket bar codes. The pattern of bars in a DNA profile shows __________.

the presence of various-size fragments of DNA There is only a very low probability that DNA bands used to provide a DNA profile would be shared by two or more individuals—with the exception of identical twins.

"Sticky ends" are very useful in genetic engineering because __________.

they provide a site for complementary base pairing so that pieces of DNA can be linked together

The so-called sticky ends of a plasmid or bacterial chromosome are __________.

unpaired bases produced by a restriction enzyme

When plasmids, which are small, circular, bacterial, DNA molecules, are used to transfer foreign DNA to other cells, the plasmid is called a _____.

vector Vectors are DNA carriers that transport genes from one cell to another.

Although it was groundbreaking for its time, it is now fairly routine to completely sequence the DNA of an organism using the ___________________________. In this method, the DNA is chopped up with restriction enzymes, the fragments are sequenced, and then they are reassembled into one continuous sequence. Through such analyses, scientists are learning much about human DNA and its relation to other species.

whole-genome shotgun method