CH 20

Cells that can take up DNA from the medium are consider

competent cells

cDNA is made using what as the starting material?

RNA

A small DNA molecule that can replicate independently within a host cell and thus make many copies of an inserted gene is called a

vector

A researcher may use restriction enzymes to digest the DNA of an organism. The fragments of DNA are then ligated individually into many vectors. This collection of recombinant vectors is called a

DNA library

DNA sequencing enables researches to determine the order of _____ _____ in a gene

DNA nucleotides

( ) DNA technology uses in vitro molecular techniques that combine DNA fragments to produce novel arrangements.

Recombinant

What does the enzyme DNA ligase do?

it covalently links the sugar-phosphate backbone of DNA

order the steps in one cycle of a PCR reaction

Denaturation Primer annealing Primer extension

Many species of bacterial cells make restriction enzymes to protect themselves from invasion by

Foreign DNA

Site-directed mutagenesis allows researchers to produce a mutation at a ______ within a cloned DNA segment.

Specific site

You would _____ a gene to make copies of that gene

clone

The replication of recombinant DNA molecules inside a host cell is one form or

gene cloning

common uses of gene cloning

* The expression of a cloned gene can be used to discover its cellular function. * Cloned genes can be introduced into bacteria to make medicines * Cloned genes can be used in trials of gene therapy

Why would you use a poly-dT primer when making cDNA?

It would be complementary to the poly-A tail at the 3' end of the mRNA

A molecule that has covalently linked DNA fragments from at least two sources is called a

Recombinant DNA molecule

To perform many cycles of PCR, you need a machine that can change temperatures at exact times.

Thermocycler

In PCR, why do the primers bind to specific sites in the DNA on either side of the gene of interest?

They are complementary to the flanking sequences

What is the purpose of Southern blotting?

To identify a particular DNA sequence within a mixture of DNA fragments

How does a bacterial cell use restriction enzymes?

To protect the cell against invasion by bacteriophages

Which procedure is used to identify a specific protein within a mixture of many different protein molecules?

Western blotting

you wish to determine if a protein is made at a particular stage of development. What technique would you use?

Western blotting

If you wanted a collection of only transcribed DNA, you would construct a

cDNA library

Making many copies of a particular DNA segment using vectors or the polymerase chain reaction is called gene

cloning

Transformation occurs when

competent cells take up DNA from the medium

In PCR, primer extension refers to the synthesis of _____ starting at the primers

complementary DNA

When DNA is made using RNA as the starting material, the DNA is called

complementary DNA

A vector requires an origin of replication so that it can be

copied many times by the host cell

Vectors that can be used to clone larger segments of DNA

cosmids, BACs, YACs

Molecular biologists use restriction enzymes to amplify a specific section of DNA within the genome.

false

A cell that harbors a vector is called a

host cell

What is the term that describes a cell that contains a DNA cloning vector?

host cell

Short oligonucleotides that flank the region to be amplified by PCR are called

primers

A vector that contains a piece of chromosomal DNA is referred as a

recombinant vector

The enzyme ____ _____ is used when PCR is employed to detect and quantify the amount of a specific RNA

reverse Transcriptase

The enzyme that uses RNA as a template to make a complementary strand of DNA is called

reverse Transcriptase

Primer annealing occurs when

short oligonucleotides bind to complementary DNA flanking the gene of interest

Allows a researcher to produce a mutation at a specific sequence

site-directed mutagenesis

The use of dideoxyribonucleotides with different colored dyes allows the detection of

the DNA sequence

What is the purpose of Northern blotting?

to identify a specific RNA molecule within a mixture of RNA molecules

Steps in a cloning gene

1. Chromosomal DNA is isolated and cut with a restriction enzyme; the plasmid DNA is cut with the same enzyme. 2. The digested chromosomal DNA and plasmid DNA are incubated together 3. Ligation by DNA ligase

Place in correct order the steps in constructing a cDNA library

1. Create complementary DNA using reverse transcriptase 2. Attach linkers to cDNA using DNA ligase 3. Cut the cDNAs and the vectors with the same restriction enzyme 4. Ligate the cDNAs and the vectors together 5. Transform recombinant vectors into host cells

Order the steps in DNA sequencing

1. Many copies of a single-stranded vector containing the gene of interests are acquired 2. Primers are added 3. High concentrations of all four unlabeled dideoxyribonucleotides and DNA polymerase are added 4. Low concentrations of all four fluorescently labeled dideoxyribonucleotides and DNA polymerase are added

Order the steps in performing a Western blot

1. Separate the proteins in a mixture using SDS-Page 2. Blot the proteins onto a nylon membrane 3. Incubate the nylon membrane with the primary antibody 4. Incubate the nylon membrane with the secondary antibody 5. Treat the nylon mesh with a reagent that causes a color change

Restriction endonucleases are used in gene cloning to

cut the DNA backbone prior to inserting the DNA to be cloned

What is a plasmid?

A small circular DNA molecule often used as a vector in gene cloning