Chapter 9 Biology

Bacterial enzymes that cut the DNA of viruses are called

restriction enzymes

Which technique is used to separate DNA fragments by their size?

gel electrophoresis

Suppose a segment of DNA contains five restriction sites for a particular restriction enzyme. How many fragments of DNA will remain after the enzyme is used to cut the DNA?


Some restriction enzymes leave behind "sticky ends," or tails of

exposed bases

What do the bands on a restriction map show?

sizes of DNA fragments

Which of the following are examples of clones?

identical twin sisters

DNA that contains genes from more than one organism is called

recombinant DNA

Scientists commonly use bacteria in genetic engineering because bacteria

can contain plasmids

Which statement is true of all genetically engineered organisms?

they have altered genomes

Plants that contain recombinant DNA are called


Which of the following statements about polymerase chain reaction (PCR) is true?

requires primers and nucleotides

The first step of PCR is to heat a DNA molecule to more than 90�C. What is the function of this step?

to separate the DNA strands

The main role of primers during the PCR process is to

provide a starting point for DNA synthesis.

During each PCR cycle, what happens to the number of copies of a DNA segment?

it doubles

Scientists use PCR primarily to

amplify DNA

Which phrase is true for a DNA fingerprint?

it is a type of restriction map

Which of the following is the basis for the molecular differences identified by DNA fingerprinting?

regions of noncoding DNA

The pattern of bands on a DNA fingerprint shows the sizes of DNA fragments related to the

number of repeat sequences

The chance that two people both have three repeat sequences at location A is 1 in 500. The chance that two people have four repeat sequences at location B is 1 in 800. What is the probability that two people have the same number of repeats in both locatio

1 in 40,000

DNA fingerprinting can be used to

prove a family relationship

The two main goals of the Human Genome Project are to sequence all of the DNA base pairs of the human chromosomes and to

identify all of the genes within the genome.

Gene sequencing defines the order of

DNA nucleotides in genes or genomes.

The study of the proteins that result from an organism's genome is called


Which of the following terms is used to describe the use of computer databases to analyze and organize biological data?


DNA microarrays can be used to compare different cell types by showing

patterns of gene expression

The main purpose of genetic screening is to

assess the risk of having or carrying a genetic disorder.

Which of the following genetic disorders can be identified through genetic screening?

cystic fibrosis

How are viruses used in gene therapy?

to carry new genes into cells

The goal of gene therapy is to replace defective or missing genes in order to

treat some genetic disorders

Which factor has so far kept gene therapy from becoming an effective treatment for genetic disorders?

the difficulty of getting new genes to become part of a cell's DNA

these cut DNA molecules when identify specific nucleotide sequences

restriction enzymes

an electrical current that is used to separate a mixture of fragments from each other

gel electrophoresis

show the length of DNA fragments between restriction sites ina strand of DNA

restriction maps

A technique that produces millions or even billions of copies of a specific DNA sequence in just a few hours

polymerase chain reaction (PCR)

short segment of DNA that acts as a starting point for a new strand


representtion of parts of an individual's DNA that can be used to identify a person at a molecular level

DNA fingerprint

genetically identical copy of a gene or an organism


the changing of an organism's DNA to give the organism new traits

genetic engineering

DNA that contains genes from more than one organism

recombinant DNA

closed loops of DNA that are separate from the bacterial chromosome and that replicate on their own within the cell.


organism has one or more genes from another organism inserted into its genome


disrupting the function of a gene

gene knockout

The study of genomes, which can include the sequencing of all of an organisms DNA.


determining the order of nucleotides in genes or genomes

gene sequencing

what are the two main goals of the Human Genome Project

- to map and sequence all of the DNA base pairs of human chromosomes
- identify all of the genes within the sequence

use of computer databases to organize and analyze biological data


Tools that allow scientists to study many genes, and their expression at once.

DNA microarrays

The study and comparison of all the proteins that result from an organisms genome.


the process of testing DNA to determine a person's risk of having or passing on a genetic disorder

genetic screening

the replacement of a defective or missing gene, or the addition of a new gene, into a person's genome to treat a disease

gene therapy

Who determined the structure of DNA?

Watson and Crick

What are some examples that have allowed advances in genetics research

chemicals, computers and bacteria

what are artificial nucleotides used for

sequencing genes

what are chemical mutagens used for

change in DNA sequences

bacteria enzymes do what

cut and copy DNA

enzymes can also be known as


the sequence of nucleotides that is identified and cut by restriction enzymes is called

restriction site