chapter 13: biotech

Question 0

restriction enzymes

Answer 0

scissors for dna

Question 1

recombinant dna

Answer 1

single molecules containing dna sequences from two or more organisms

Question 2

gel electrophoresis

Answer 2

analysis/purification/organization by length of dna fragments

Question 3

dna ligase

Answer 3

joins dna fragments

Question 4

recognition sequence

aka restriction site

Answer 4

• specific series of bases where restriction enzymes cut the dna
• usually 4-6 base pairs long
• palindromes: same forward/backwards

Question 5

sticky ends

Answer 5

able to form hydrogen bonds with complementary sequences

Question 6

blunt ends

Answer 6

bad for joining

use for analysis for research

Question 7

restriction digest

Answer 7

the process of using restriction enzymes in the lab to cut sample dna

Question 8

knowledge from gel electrophoresis

Answer 8

• number of fragments
• sizes of fragments
• relative abundance of fragments

Question 9

transformation/transfection

Answer 9

cloning recombinant dna by inserting if into host cell

Question 10

transgenic cell/organism

Answer 10

used as host for recombinant dna

Question 11

selectable marker genes

Answer 11

used so that only the transgenic cells grow

Question 12

electroporation

Answer 12

electric shocks are used to open temporary pores in membrane that allow dna to enter

Question 13

how dna becomes a part of the replicon

Answer 13

• inserted into host chromosome

- enters through a vector

Question 14

plasmids

Answer 14

• small, circular dna molecules that replicate in prokaryotic cells
• used as transformation vectors
• often serve as selectable markers too

Question 15

reporter gene

Answer 15

any gene whose expression is easily assayed

ex: selectable markers, glow in the dark gene

Question 16

genomic library

Answer 16

collection of dna fragments that comprises the genome of an organism

Question 17

cDNA library

Answer 17

• made of complementary dna

- a snapshot of transcription

Question 18

knockout experiment

Answer 18

to knockout genes by inactivating them so that they cannot be transcribed/translated

Question 19

homologous recombination

Answer 19

• a way of knocking out a gene
• reporter gene interrupts gene so that it no longer creates a functional gene
• recombinant plasmid is made and used to specify stem cells
• if recombination occurs, the inactive allele is replaced by an allele of the host cell

Question 20

antisense RNA

Answer 20

binds to mrna and inhibits trnanslation

often used as drugs

Question 21

RNA interference (RNAi)

Answer 21

• natural mechanism
• small interfering rnas (siRNA)
• gene knockdown

Question 22

expression vectors

Answer 22

vectors with extra sequences for the transgene. can include:

• inducer promoter
• tissue specific promoter
• signal sequences

Question 23

Advantages of recombinant dna tech

Answer 23

• ability to identify specific genes
• ability to introduce any gene from any organism into a plant/animal species
• ability to generate new organisms quickly

Question 24

public concern over biotech

Answer 24

• its an unnatural interference with nature
• altered foods are unsafe to eat
• dangerous to environment