F215 2.2 - Biotechnology Flashcards
Biotechnology
Use of microorganisms or their products/processes to generate useful products.
Fermentation
Process of culturing any microorganism either aerobically or anaerobically in order to generate a specific product.
Binary fission
Main method by which bacteria reproduce
Metabolites
Substance formed during a metabolic reaction
Batch culture
A culture of microorganisms that takes place in a single fermentation. Products are separated from the mixture at the end of the fermentation process.
Continuous culture
A culture of microorganisms set up in a reaction vessel to which substrates are added and from which products are removed a fermentation continues.
Primary metabolites
Formed as part of the normal growth of a microorganism. e.g. lipids, proteins, carbohydrates and waste products
Secondary metabolites
Produced by some microorganisms in the latter stages of growth. Often have antibiotic properties.
Sigmoid growth curve
Growth pattern typical of most microorganisms kept in a culture vessel where nutrient supplies are limiting.
Lag phase
Initial stages of growth of a culture of microorganisms in which synthesis of enzymes for the conditions in which they are growing takes place
Log phase
Stage of growth of a culture of microorganisms in which their numbers double at regular intervals. Occurs whilst nutrients, oxygen and space are not limiting factors.
Stationary phase
Stage of growth of a population in a closed culture where reproductive rate equals the death rate, so population size remains constant. Occurs when an environmental factor becomes limiting
Decline phase
Stage of growth in a population in a closed culture in which death rate exceeds reproductive rate
Asepsis
Without contamination by unwanted microorganisms
Contaminant (microoganisms)
Growth of an unwanted microorganism in a culture
