Molecular Genetics Analysis And Biotechnology

Question 2

Cohesive (“sticky”) End

Answer 2

Short, single-stranded overhanging end on a DNA molecule produced when the DNA is cut by certain restriction enzymes. These are complementary and can spontaneously pair to rejoin DNA fragments that have been cut with the same restriction enzyme.

Question 3

Restriction Enzyme Or Restriction Endonuclease

Answer 3

Enzyme that recognizes particular base sequences in DNA and makes double-stranded cuts at those sequences.

Question 4

Biotechnology

Answer 4

Use of biological processes, particularly molecular genetics and recombinant DNA technology, to produce products of commercial value.

Question 5

Recombinant DNA Technology Or Genetic Engineering

Answer 5

Set of molecular techniques for locating, isolating, altering, combining, and studying DNA segments.

Question 6

Blunt (Non-Cohesive) End

Answer 6

Both strands of DNA are of equal length (they end at the same base position, leaving no unpaired bases on either strand).

Question 7

Engineered Nuclease

Answer 7

Protein consisting of the part of a restriction enzyme that cleaves DNA, combined with another protein that recognizes and binds to a specific DNA sequence; capable of making unique double-stranded cuts in DNA at predetermined sequences. These can be custom designed to bind to and cut any particular DNA sequence.

Question 8

Cas9

Answer 8

a CRISPR-associated endonuclease that acts as “molecular scissors” to cut DNA at a location specified by a guide RNA.

Question 9

Guide RNA

Answer 9

an RNA molecule that binds to Cas9 and specifies, based on its sequence the location at which Cas9 will cut DNA.

Question 10

CRISPER-Cas System

Answer 10

A molecular tool whereby genes are edited by precisely cutting DNA and then letting natural DNA repair processes repair the break. The system consists of two parts: the Cas9 enzyme and a guide RNA.

Question 11

Gel Electrophoresis

Answer 11

Technique for separating charged molecules (such as proteins or nucleic acids) on the basis of molecular size or charge, or both.

Question 12

Gene Cloning

Answer 12

Insertion of DNA fragments into bacteria in such a way that the fragments will be stable and will be copied by the bacteria.

Question 13

Primer

Answer 13

a short stretch of RNA on a DNA template; provides a 3’OH group for the attachment of a DNA nucleotide at the initiation of replication.

Question 14

Polymerase Chain Reaction (PCR)

Answer 14

Method of enzymatically amplifying DNA fragments.

Question 15

Cloning Vector

Answer 15

Stable, replicating DNA molecule to which a foreign DNA fragment can be attached for introduction into a cell.

Question 16

Taq Polymerase

Answer 16

DNA polymerase commonly used in PCR reactions. Isolated from the bacterium Thermus aquaticus, the enzyme is stable at high temperatures, so it is not denatured during the strand-separation step of the cycle.

Question 17

Cosmid

Answer 17

A cloning vector consisting of a plasmid packaged in a viral protein coat that can be transferred to bacteria by viral infection; can carry large pieces of DNA into bacteria.

Question 18

DNA Library

Answer 18

Collection of clones containing all the DNA fragments from one source.

Question 19

Expression Vector

Answer 19

Cloning vector containing DNA sequences such as a promoter, a ribosome-binding site, and transcription initiation and termination sites that allow DNA fragments inserted into the vector to be transcribed and translated.

Question 20

cDNA (Complementary DNA) Library

Answer 20

Collection of bacterial colonies or phages containing DNA fragments that have been produced by reverse transcription of cellular mRNA.

Question 21

Genomic Library

Answer 21

Collection of bacterial colonies or phages containing
DNA fragments that constitute the entire genome of an organism.

Question 22

Bacterial Artificial Chromosome (BAC)

Answer 22

Cloning vector originally constructed from the F plasmid that can hold very large fragments of DNA (as long as 300,000 bp).

Question 23

DNA Sequencing

Answer 23

Process of determining the sequence of bases along a DNA molecule.

Question 24

Probe

Answer 24

A DNA or RNA molecule with a base sequence that is complementary to a sequence of interest and will pair with it; used to find specific DNA sequences.

Question 25

Dideoxyribonucleoside triphosphate (ddNTPs)

Answer 25

Special substrate for DNA synthesis used in the Sanger sequencing method; identical with dNTP (the usual substrate for DNA synthesis) except that it lacks a 3′-OH group. The incorporation of a ddNTP into DNA terminates DNA synthesis.

Question 26

Next-generation sequencing technology

Answer 26

Sequencing methods that are capable of simultaneously determining the sequences of many DNA fragments; these technologies are much faster and less expensive than the Sanger dideoxy sequencing method.

Question 27

Third Generation Sequencing Technology

Answer 27

New sequencing technologies that determine the sequence of single DNA or RNA molecules and allow longer fragments to be sequenced.

Question 28

DNA fingerprinting

Answer 28

Technique used to identify individuals by examining their DNA sequences.

Question 29

microsatellite

Answer 29

Very short DNA sequence repeated in tandem; also called a short tandem repeat (STR).

Question 30

forward genetics

Answer 30

Traditional approach to the study of gene function that begins with a mutant phenotype and proceeds to a gene that encodes the phenotype.

Question 31

reverse genetics

Answer 31

A molecular approach to the study of gene function that begins with a genotype (a DNA sequence) and proceeds to the phenotype by altering the sequence or by inhibiting its expression.

Question 32

transgene

Answer 32

Foreign gene or other DNA fragment carried in germ-line DNA.

Question 33

knockout mouse

Answer 33

Mouse in which a normal gene has been fully disabled (knocked out).

Question 34

knock-in mouse

Answer 34

Mouse that carries a foreign DNA sequence inserted at a specific chromosome location.

Question 35

gene therapy

Answer 35

The direct transfer of genes into human patients to treat disease.

Question 36

multiple cloning site

Answer 36

A short segment of DNA which contains many restriction sites and is a standard feature of engineered plasmids.

Question 37

selectable marker

Answer 37

A gene that is introduced into a cell that confers a trait suitable for artificial selection.