Environmental control of metabolism

Question 1

What are some types of micro-organisms

Answer 1

Archaea, bacteria and some species of eukaryotes

Question 2

Describe micro-organisms

Answer 2

They have a wide variety for substrates and produce a range of products from their metabolic pathways

Question 3

Why are micro-organisms used

Answer 3

Their adaptability, ease of cultivation and speed of growth

Question 4

What do micro organisms require during culturing

Answer 4

their growth media requre raw materials for biosynthesis and an energy source

Question 5

What can energy sources be derived from

Answer 5

chemical substrates or from light in photosynthetic micro organisms.

Question 6

What are 4 important conditions for culturing

Answer 6

Sterility and control of ph, temperature and oxygen levels.

Question 7

Why are sterile conditions required

Answer 7

Reduce competition between desired and non-desired micro-organisms, reduce risk of spoilage of product

Question 8

Describe the lag, log, stationary and death phase in culturing

Answer 8

Lag: Enzymes are introduced to metabolise substrates
Log: Most rapid growth of micro-organisms due to lots of nutrients
Stationary: Nutriets depleted, production of toxic metabolites (secondary metabolites such as antibiotics are also produced, in the wild these hold an advantage by allowing the micro-organisms which produce them to outcompete others.)
Death: Accumulation of toxic metabolites or lack of nutrients