The Good, Bad, Ugly of Bact Flashcards
What is nitrogen fixation
The process by which molecular nitrogen is reduced to form ammonia
What in the body are usually free of microorganisms
Internal tissues - blood, brain, muscle etc
How many bacteria does the normal human flora contain
More than 200
What does the normal flora gain from the human host
- Supply of nutrients
- Stable environment
- Constant temp
- Protection
- Transport
What does the human host gain from the normal flora
- Nutritional benefits
- Stimulation of immune system
- Colonization strategies that exclude potential pathogens at the site
- (E. coli in human colon synthesises vit B & releases it for human use)
Homofermentors
Single product - lactic acid
Heterofermentors
Multiple products - - lactic acid, ethanol, CO2
What is bioremediation
Any process that uses microorganisms, fungi, green plants or their enzymes to return the environment altered by contaminants to its original condition
(Bacteria used to break down sewage wastes)
Biotechnology definition and examples
Defined as the application of organisms such as bacteria, fungi, algae to the manufacturing & services industries
* Fermentation processes - Lactobacillus used in prep of fermented foods
* Chemical manufacturing - ethanol, acetone, organic acid
* Pharmaceuticals - antibiotics, vaccines
* Energy - biogas
* Food products - dairy products, amino acids & proteins
How are genes introduced into the host in genetic engineering
By means of a carries (vector)
HOw does genetic engineering work
- Genes introduced into host by means of a vector
- Foreign DNA becomes permanent feature of host, being replicated & passed on to daughter cells
- Bacterial cells transformed & used in production of important products
- Can be engineered to produce insulin, growth factors, antibodies
Decomposition: what is autolysis
The breaking down of tissues by the bodys own internal chemicals and enzymes
Decompostion: what is putrefaction
The breakdown of tissues by bacteria
Opportunistic pathogens
Cause damage when immune system is breached
What bacteria causes tooth decay
Streptococcus mutans
Where is S. aureus present in 30% of population
Nasal passages
When can S. aureus causes serious infection
When innate immune system is breached
Function of biofilm
- Protects bacteria from washing away
- Slime protects from antibiotic & immune system
What can invasive streptococcal infections develop into
Necrotising faciitis (flesh-eating bacteria)
Toxin that causes botulism
Clostridium botulinium
What does Clostridium botulinium do
Bonds to presynaptic stimulatory terminals & blocks the release of neurotransmeitter acetylcholine - required for a nerve to stimulate the muscle
Clinical symptoms of botulism
- Weakness
- Dizziness
- Dryness of mouth
- Nausea & vomiting
- Neurologic features - blurred vision, inability to swallow, difficulty in speech
What is the botulism toxin specific for
For peripheral nerve endings at the point where a motor neuron stimulates a muscle
Epidemiology
The study of factors affecting health & illness of populations. (outbreak investigation, study design, analysis, test hypotheses)
