Microorganisms

Question 1

Describe a closed culture

Answer 1

the microorganisms in a fermenter do not have any exchange of nutrients or gases with the external environment. eg a batch culture

Question 2

Describe the phases shown in a batch culture

Answer 2

1 is the lag phase. 2 is the log phase. 3 is the stationary phase and 4 is the decline phase

Question 3

How are Primary metabolites made?

Answer 3

produced during the log phase as they are made in continuous culture

Question 4

Continuous culture conditions …

Answer 4

conditions are altered continuously to allow for optimal growth

Question 5

How are secondary metabolites made?

Answer 5

produced during the stationary phase when there are not enough nutrients for the whole population. This is because they are produced in stressful conditions and are therefore made in closed culture

Question 6

Why are Microorganisms used in biotechnology?

Answer 6

they’re cheap, have a rapid growth rate, easily genetically modified, need simple nutrient, secrete products and make their own enzymes

Question 7

What is Bioremediation …

Answer 7

the process in which microorganisms are used to clear toxic pollutants by converting them to less harmful substances

Question 8

features of Comercial drug production with microorganisms …

Answer 8

takes place on a large-scale using fermenters, as this allows for certain conditions to be carefully controlled so that a high yield is obtained

Question 9

The fungus Fusarium veneatum directly produces …

Answer 9

mycoprotein, also known as single-cell protein (SCP)

Question 10

Why are sterile conditions required in cultures

Answer 10

to prevent the growth of unwanted microorganisms which can reduce yield or produce toxins, killing the cultured microorganisms and destroying their products