Biotechnology

Question 1

Two mediums for growing microorganisms

Answer 1

• nutrient broth
• agar jelly (microorganisms form colonies)

Question 2

cultures of microorganisms can be used to investigate…

Answer 2

antibiotic
disinfectants

Question 3

Aseptic technique conditions 4 areas

Answer 3

• max temp 25°c
• flames
• lids quickly placed and upside-down (prevent condensation from forming and falling onto agar)
• boiling agar and nutrient solutions (avoid contamination)

Question 4

Apparatus used to spread culture

Answer 4

innoculation loop

Question 5

bacteria divide roughly…

Answer 5

every 20 mins

Question 6

plasmids are useful because

Answer 6

can be manipulated to contain particular genes

Question 7

pros of using microorganisms in biotech

Answer 7

• cheap
• metabolise waste products so can reduce
• less space required

Question 8

cons of using microorganisms in biotech

Answer 8

• bad taste
• high startup costs

Question 9

Bioremediation

Answer 9

microorganisms used to break down pollutants

Question 10

Stages of growth of bacterial colonies

Answer 10

Lag phase, Log phase, stationary phase, death phase

Question 11

lag phase

Answer 11

bacteria adapting to new environment, making enzymes they need

Question 12

Log phase

Answer 12

rate of bacterial growthat maximum

Question 13

stationary phase

Answer 13

total growth rate at zero. cells formed= cells died

Question 14

limiting factors that prevent exponential growth

Answer 14

• O2 levels
• temp
• nutrients available
• buildup of toxic material
• change in pH

Question 15

serial dilutions- how to find totsl cell count per volume of original colony

Answer 15

multiply number of colonies by dilution factor

Question 16

primary metabolites example

Answer 16

quorn

Question 17

primary metabolites harvesting method- and bacterial stage

Answer 17

continuous fermentation, produced during log phase

Question 18

Secondary metabolites example

Answer 18

penicillin

Question 19

Secondary metabolites harvesting and production

Answer 19

batch phase, produced in stationery phase

Question 20

asepsis

Answer 20

bioreactors are sealed off to prevent contaminants from air

Question 21

entrapment

Answer 21

• enzymes held within network of fibres
• not joined by covelant bonds to the cellulose

Question 22

covelant bonding

Answer 22

• covelant bonding between enzyme and insoluble substrate

Question 23

Memrane seperation/ membrane entrapment/ encapsulation

Answer 23

• enzymes behind semi-permeable membrane

Question 24

Adsorption

Answer 24

• enzymes bind to surface of adsorption agent
• held by ionic and hydrophobic interactions

Question 25

example of adsorption

Answer 25

alginate beads

Question 26

example of encapsulation

Answer 26

polymer based semi permeable membrames

Question 27

example of covelant bonding

Answer 27

carries with amino, hydroxy, carboxyl groups

Question 28

entrapment examples

Answer 28

gelatin

Question 29

Benifits of some immobilisation

Answer 29

- can buffer changes in environment - reduce costs of extraction