What is batch fermentation?

A process where microorganisms are added to a fixed volume of nutrient medium in a closed system, allowed to grow until nutrients are depleted, then the entire contents are harvested.

What is continuous fermentation?

A process where fresh nutrient medium is constantly added and culture fluid containing product is continuously removed, maintaining the culture in exponential growth phase.

Why is temperature controlled during fermentation?

To maintain optimal enzyme activity and metabolic rate of the microorganisms for maximum product yield.

Why is pH monitored and adjusted during fermentation?

To maintain optimal conditions for enzyme function, as pH changes can denature enzymes and reduce yield.

Why is oxygen supply important in aerobic fermentation?

Aerobic microorganisms require oxygen for respiration; insufficient oxygen limits growth and product formation.

OCR A-Level Biology H420

Cell Structure

Topic overview Microscopy, slide preparation and staining Biological drawings, magnification and resolution Eukaryotic cell ultrastructure The secretory pathway and the cytoskeleton Prokaryotic and eukaryotic cells compared

Biological Molecules

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Communicable Diseases, Disease Prevention and the Immune System

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Cellular Control

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Cloning and Biotechnology

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Cloning and Biotechnology

Fermentation and its conditions

1 thing to know
Components 02 and 03

Overview

Batch and continuous fermentation, and why temperature, pH, oxygen supply, nutrient concentration and agitation are monitored and controlled.

What you need to know

Answer each one before you reveal it.

Your recallNot started

Key term

Why is nutrient concentration monitored during fermentation?

Questions from this subtopic

Each one with the model answer underneath.

1
What is batch fermentation?
Model answer
A process where microorganisms are added to a fixed volume of nutrient medium in a closed system, allowed to grow until nutrients are depleted, then the entire contents are harvested.
2
What is continuous fermentation?
Model answer
A process where fresh nutrient medium is constantly added and culture fluid containing product is continuously removed, maintaining the culture in exponential growth phase.
3
Why is temperature controlled during fermentation?
Model answer
To maintain optimal enzyme activity and metabolic rate of the microorganisms for maximum product yield.
4
Why is pH monitored and adjusted during fermentation?
Model answer
To maintain optimal conditions for enzyme function, as pH changes can denature enzymes and reduce yield.
5
Why is oxygen supply important in aerobic fermentation?
Model answer
Aerobic microorganisms require oxygen for respiration; insufficient oxygen limits growth and product formation.
6
Why is nutrient concentration monitored during fermentation?
Model answer
To ensure microorganisms have sufficient substrates for growth and product synthesis.

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AA phospholipid contains one glycerol molecule.

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