Chapter 11 Biotechnology

Question 1

DNA template

Answer 1

the DNA segment to be amplified

Question 2

DNA polymerase

Answer 2

to catalyse the formation of new DNA molecules by joining together free nucleotides

Question 3

Primer

Answer 3

single stranded DNA molecule
-acts as the start of the amplification process

Question 4

Agarose gel

Answer 4

gel matrix used for electrophoresis

Question 5

Visualising DNA

Answer 5

DNA is not visible in the gel, so a dye must be used
-Ethium bromide is a UV fluorescent dye that binds to DNA and is used to visualise DNA

Question 6

DNA profiling/DNA fingerprinting e.g

Answer 6

crime scenes, paternity/maternity

Question 7

Steps in making recombinant DNA

Answer 7

-isolation of genetic material
-cutting the gene at the recognition sits
-amplifying gene copies through PCR
-ligation of DNA molecules
-insertion of recombinant DNA into host

Question 8

restriction enzymes

Answer 8

enzymes of a bacterial origin that cut DNA at a specific restriction site

Question 9

DNA sequencing process

Answer 9

4 nucleotides are labelled with different coloured fluorescent dyes

Question 10

Denaturation

Answer 10

double stranded DNA template needs to be separated
-DNA is heated to ~95 degrees to break hydrogen bonds
i.e melting stage

Question 11

Annealing

Answer 11

Temperature is reduced to 50-60 degrees, allowing the forward and reverse primers to anneal (join) to the complementary sequence

Question 12

Steps in DNA profiling

Answer 12

1. DNA to be profiled is isolated from any somatic cell with a nucleus
2. PCR is used to amplify the DNA of up to 20 different STR regions
3. Amplified DNA is then separated by gel electrophoresis

Question 13

PCR cycling steps

Answer 13

1. Denaturation
2. Annealing
3. Elongation

Question 14

Elongation

Answer 14

-Temp is raised to 72 degrees -> optimal temp for taq polymerase
-new DNA strands are synthesised using free nucleotides

Question 15

gel electrophoresis

Answer 15

technique that separates DNA fragments according to their size and charge

Question 16

DNA profiling

Answer 16

process that is able to identify natural variations that exist within an individuals genome, by using PCR and gel electrophoresis

Question 17

DNA ligase

Answer 17

-Enzyme used to catalyse the formation of a bond between two pieces of DNA
-used to insert a gene into plasmids

Question 18

Plasmid vectors

Answer 18

-to transport genes of interest from one organisms into another
-plasmids reproduce independently of the bacterial chromosome

Question 19

taq polymerase

Answer 19

-DNA polymerase from the bacterium
-used in PCR
-can withstand high temp used in the PCR process