Manipulating Genomes

Question 1

DNA sequencing

Answer 1

a technique that allows genes to be isolated and read

Question 2

autoradiograms

Answer 2

photographs made when photographic film is exposed to molecules labelled with radioactivity

Question 3

activated nucleotide

Answer 3

a nucleotide with 2 extra phosphoryl groups

Question 4

in pyrosequencing, the amount of light generated

Answer 4

is proportional to the amount of ATP available so indicated how many of the same type of activated nucleotide were incorporated adjacently into the cDNA

Question 5

bioinformatics

Answer 5

branch of biology that deals with storing, displaying and using large quantities of complex data

Question 6

methylation

Answer 6

addition of methyl (CH3) groups to a molecule- it plays a major role in regulating gene expression to map human genomes and understand diseases/cancer

Question 7

polymorphism

Answer 7

having more than one form- may refer to variations within the DNA sequences of a gene

Question 8

polymerase chain reaction (PCR)

Answer 8

a biomedial technology in molecular biology that can amplify a short length of DNA to millions of copies

Question 9

PCR relies on the fact that

Answer 9

DNA has 2 antiparallel backbones, each strand has a 5’ end/3’ end, DNA only grows from 3’ end, bases pair up according to complementary pairing rules

Question 10

PCR differs from DNA replication in that

Answer 10

only short sequences (not chromosomes) can be replicated, requires the addition of a primer to make process start, cycle of heating/cooling to separate DNA strands

Question 11

primers

Answer 11

short (10-20 base pairs) single-stranded sequences of DNA needed for sequencing reactions and PCR

Question 12

electrophoresis

Answer 12

process used to separate proteins or DNA fragments of different sizes

Question 13

DNA ligase

Answer 13

catalyses the joining of sugar and phosphate groups by a condensation reaction within DNA

Question 14

electroporation

Answer 14

method for introducing a vector with a novel gene into a cell- pulse of electricity make the recipient cell membrane more porous

Question 15

plasmids

Answer 15

small loops of DNA in prokaryotic cells

Question 16

recombinant DNA

Answer 16

composite DNA molecule created in vitro by joining foreign DNA with a vector molecule such as a plasmid

Question 17

restriction enzymes

Answer 17

endonuclease enzymes that cleave DNA molecules at specific recognition sites- they cut up foreign viral DNA

Question 18

vector

Answer 18

in gene technology, anything that can carry/insert DNA into a host organism

Question 19

reverse transcriptase

Answer 19

retroviruses (HIV) which contain RNA that they inject into the host genome, have this to catalyse the production of cDNA using RNA as a template

Question 20

germ line therapy

Answer 20

gene therapy by inserting functional alleles into gametes or zygotes

Question 21

somatic cell gene therapy

Answer 21

gene therapy by inserting functional alleles into body cells

Question 22

principle of gene therapy

Answer 22

insert a functional allele of a particular gene that contain only mutated/non-functioning alleles so it will produce a functioning proteins and no longer have symptoms of the genetic disorder