6. Environmental Control of Metabolism - Culture Conditions Microorganism

Question 1

How can the metabolism of microorganisms be manipulated?

Answer 1

By altering growth medium, environmental conditions or genetic control

Question 2

Describe the composition of growth medium

Answer 2

Growth medium can contain specific substances (eg glucose, nitrate) or complex mixtures (eg beef extract), depending upon organism being cultured

Question 3

What are the energy sources used by microorganisms to cultivate?

Answer 3

chemical substances or light for photosynthetic microorganisms and raw materials for biosynthesis

Question 4

Many species of microorganism can produce…

Answer 4

all the complex molecules required including all the amino acids from simple chemical compounds

Question 5

Some species of microorganism require what to culture?

Answer 5

Complex molecules such as vitamins or fatty acids

Question 6

Why must culture conditions be sterile?

Answer 6

To eliminate any effects of contaminating microorganisms

Question 7

Name some ways that abiotic conditions are controlled during culture

Answer 7

control of temperature by cooling jacket
control of oxygen levels by aeration
control of pH by buffers or addition of acid/alkali
aseptic technique to minimise contamination