Unit 4 AOS 2: DNA manipulation

Question 1

Anneal

Answer 1

The joining together of DNA or RNA fragments by complementary base pairing

Question 2

Bacterial transformation

Answer 2

The incorporation of DNA from another organism into a bacterial cell

Question 3

Bacteriophage

Answer 3

A virus that infects bacteria

Question 4

Blunt-end restriction enzyme

Answer 4

A restriction enzyme that leaves clean-cut ends because it cuts both strands of the DNA molecule at the same location within the recognition site

Question 5

Complementary DNA (cDNA)

Answer 5

Double-stranded DNA that contains no introns; copied from mRNA by the enzyme reverse transcriptase

Question 6

DNA amplification

Answer 6

The process of creating millions of identical copies of a DNA sample using the PCR reaction

Question 7

DNA ladder

Answer 7

DNA standards; a set of DNA molecules of known size used as a ‘molecular ruler’ on gel electrophoresis to determine the size of other DNA molecules

Question 8

DNA ligase

Answer 8

An enzyme that joins together fragments of DNA by forming a phosphodiester bond between the 3-hydroxyl and 5-phosphate of adjacent nucleotides

Question 9

DNA polymerase

Answer 9

An enzyme that catalyses the formation of polymers of DNA by linking nucleotides into a chain by complementary base pairing with a template strand

Question 10

DNA thermocycler

Answer 10

The machine used in the polymerase chain reaction (PCR) that alters the temperature in pre-programmed steps

Question 11

Endonuclease

Answer 11

An enzyme, also called a restriction enzyme, that occurs naturally in bacteria and can cut DNA at a particular site (a recognition site); used in genetic engineering

Question 12

Gel electrophoresis

Answer 12

A technique used for separating fragments of DNA, or different proteins, based on their molecular weight (or length). Fragments migrate through a gel at rates that are dependent on their length and charge

Question 13

Gene cloning

Answer 13

The production of identical copies of a gene

Question 14

Helicase

Answer 14

A type of enzyme that unwinds and unzips the two strands of a DNA molecule

Question 15

Inducer

Answer 15

A molecule that regulates gene expression

Question 16

lacZ gene

Answer 16

A gene in the lac operon that codes for beta-galactosidase; used in recombinant plasmids for detecting transformed bacteria

Question 17

Ligase

Answer 17

An enzyme that joins together two molecules or fragments of molecules

Question 18

Ligation

Answer 18

The process of joining two fragments of DNA using a DNA ligase enzyme

Question 19

Microsatellite

Answer 19

A short repeated sequence of nucleotides found at a defined locus on a chromosome. The number of repeats varies between individuals and so are useful in DNA profiling

Question 20

Plasmid

Answer 20

Small, circular pieces of double-stranded DNA found in bacterial cells. Plasmids replicate independently of the bacteria’s chromosomal DNA and are used in genetic engineering for creating recombinant DNA

Question 21

Polymerase

Answer 21

A group of enzymes that catalyse the formation of polymers, in particular, the formation of nucleic acid polymers by complementary base pairing with a template strand

Question 22

Polymerase chain reaction (PCR)

Answer 22

A laboratory technique used to amplify (make millions of copies of) a piece of DNA in a short period of time

Question 23

Polymorphism

Answer 23

Genetic variation within a population. The least common allele has to have a frequency in a population of 1% or more to be considered polymorphism rather than mutation

Question 24

Primer

Answer 24

A short strand of DNA or RNA that is able to bind or anneal to single-stranded DNA to create a region where DNA polymerase can join and initiate DNA synthesis

Question 25

Recognition site

Answer 25

The short sequence of DNA bases recognised an cut by a restriction enzyme; also called a restriction site

Question 26

Recombinant DNA

Answer 26

DNA that has been genetically engineered by joining fragments of DNA from two or more different organisms

Question 27

Recombinant plasmid

Answer 27

A plasmid containing a foreign gene that has been inserted by the use of restriction enzymes and DNA ligase

Question 28

Restriction enzyme

Answer 28

A type of enzyme also called an endonuclease, that occurs naturally in bacteria and can cut DNA at a particular site (a recognition site); used in genetic engineering

Question 29

Reverse transcriptase

Answer 29

A type of polymerase enzyme used by retroviruses to copy their RNA genome into DNA; used in genetic engineering to copy messenger RNA (mRNA) into complementary DNA (CDNA)

Question 30

RNA ligase

Answer 30

A ligase enzyme that joins together fragments of RNA

Question 31

Sticky-end restriction enzyme

Answer 31

A type of restriction enzyme that makes a staggered cut in DNA to leave fragments with overhanging (or 'sticky') ends. The exposed bases of these sticky ends are then able to form complementary base pairs with nucleotides of other DNA molecules that have been cut with the same restriction enzyme

Question 32

Taq polymerase

Answer 32

A type of heat-resistant DNA polymerase that is widely used in PCR

Question 33

Thermophilic

Answer 33

Of or relating to an organism that favours high temperatures (a thermophile)

Question 34

Transformed

Answer 34

A bacterium that has incorporated DNA from another organism into its own or taken up a plasmid containing foreign DNA

Question 35

Gene expression

Answer 35

The expression of reading the information stored within a gene to create a functional product, typically a protein

Question 36

Transformation

Answer 36

The process by which bacteria take up foreign DNA from their environment. Scientists use this process to introduce recombinant plasmids into bacteria

Question 37

Vectors

Answer 37

An organism that is not affected by a disease but spreads it between hosts

Question 38

Social Implications

Answer 38

Consequences that affect economics, politics or society

Question 39

Biological implications

Answer 39

Consequences that affect ecosystems, environments or public health

Question 40

Ethical Implications

Answer 40

Considerations based on moral or religious beliefs

Question 41

Transgenic organism

Answer 41

A type of GMO that contains genetic material from another species that has been artificially introduced

Question 42

GMOs | Genetically modified organism

Answer 42

An organism with genetic material that has been altered using gene engineering technology

Question 43

Epidemic

Answer 43

A dramatically increased occurrence of a disease in a particular community at a particular time

Question 44

Pandemic

Answer 44

An epidemic that has spread across multiple countries and/or continents

Question 45

Cloning

Answer 45

To make a genetically identical organism or section of DNA

Question 46

DNA profiling

Answer 46

The process of identification using genetic information. Also known as DNA fingerprinting

Question 47

Rational drug design

Answer 47

A process in which scientists study the shape and charge of a target molecule and design a complementary-shaped drug that gives rise to a therapeutic benefit