2.6 environmental control of metabolism

Question 1

Different types of microorganisms

Answer 1

Bacteria
Archaea
Eukaryotes

Question 2

Microorganisms features

Answer 2

They have high adaptability
They are easy to cultivate
They have a fast growth speed.

Question 3

Reason for using microorganisms

Answer 3

Some organisms can’t produce their own essential starting materials, so microorganisms produce these starting materials, so the other organisms can produce products that are essential for the other organisms survival

Question 4

Examples of molecules produced by microorganisms

Answer 4

Amino acids
Vitamins
Fatty acids.

Question 5

Growth media definition

Answer 5

Where an ideal environment is provided for microorganisms containing the raw materials and energy for the microorganisms to successfully grow.

Question 6

Examples of growth media

Answer 6

Broth
Agar jelly

Question 7

Broth

Answer 7

A liquid medium that allows microorganisms to grow, by providing energy and nutrients to the microorganisms.

Question 8

Agar jelly

Answer 8

A solid medium that allows microorganisms to grow which has essential nutrient added to the jelly.

Question 9

How do microorganisms gain energy

Answer 9

Chemical substances
Or light if photosynthetic

Question 10

How is growth media used

Answer 10

To provide raw materials and energy to allow microorganisms to grow.

Question 10

How is growth media used

Answer 10

To provide raw materials and energy to allow microorganisms to grow.

Question 11

Examples of molecules produced by microorganisms

Answer 11

Vitamins
Fatty acids
Amino acids

Question 12

Reasons to use micro organisms

Answer 12

To produce essential starting materials for organisms who cannot produce their own starting materials.

Question 13

Fermenter definition

Answer 13

A container where microorganisms can grow in large quantities, which uses computers and probes to ensure optimum and desirable conditions for microorganisms are achieved.

Question 14

Culture conditions (different methods of increasing microorganisms yield

Answer 14

Sterility
Temperature
Oxygen level
pH

Question 15

Sterility

Answer 15

Killing off competitor microorganisms - reduces spoiling products and increases microorganisms success.

Question 16

Temperature

Answer 16

Ensures that enzyme activity is at an optimum and therefore growth is at optimum.

Question 17

Oxygen levels

Answer 17

Ensures microorganisms can undergo respiration at optimum rate.

Question 18

pH

Answer 18

Ensure microorganisms conditions are acid/alkaline to suit them.

Question 19

Growth curve

Answer 19

A graph which shows the number of microorganisms (log) and the time.

Question 20

Phases of growth curves

Answer 20

Lag
Log
Stationary
Death

Question 21

Lag phase

Answer 21

The graph stays flat
Little or no increase in cell number
Enzymes are induced to metabolise substrates

Question 22

Log phase

Answer 22

Graph goes up
Cells grow and multiply at maximum rate providing no factors are limited.
Rapid growth due to plentiful nutrients.
New cells produced exceeds death rate.

Question 23

Stationary phase

Answer 23

Graph goes flat
Nutrients in the culture become depleted or toxic metabolites are produced
Rate of new cells produced equals death rate.

Question 24

Death phase

Answer 24

The graph goes down
Cells die due to a lack of nutrients or toxic metabolites accumulating
Death rate exceeds rate of new cells produced

Question 25

Semi logarithmic scales

Answer 25

Used to show growth curves - with an x axis which is linear and a y axis which is logarithmic (goes up in powers)

Question 26

Types of cell count

Answer 26

Total cell count
Viable cell count