1 The History and Scope of Microbiology Flashcards
Scientific study of organisms (both eukaryotes and prokaryotes) and agents too small to be seen clearly by the unaided eye.
Derived from the Greek word “ mikros ” - ‘small’ , “ bios ” - ‘life’ and “logy” – study of.
These organisms are ubiquitous in nature.
MICROBIOLOGY
example of microbes or microorganisms
Viruses
Bacteria
Fungi
Algae
Protozoa
major categories of microbes
acellular
cellular
mechanism by which microbes inherit genes
Microbial genetics
structure and function (expression) of genes
Molecular biology
inserting a missing gene or replacing a defective one in
human cells
Gene therapy:
In the ____ new discoveries in
microbiology led to the development of recombinant DNA technology and genetic engineering
1970
studies the system of body defenses that protects against infection.
Immunology
aim to monitor and control
the spread of diseases in communities
Public health microbiology and
epidemiology
examine the ecological and practical roles of microbes in
food and water
Food microbiology, dairy microbiology,
and aquatic microbiology
is The relationships concerned with
between microbes and crops, with an emphasis on improving yields and combating plant diseases.
Agricultural microbiology
includes any process in which humans use the metabolism of living things to arrive at a desired
product, ranging from bread making to gene therapy
Biotechnology
is concerned with the uses of microbes to produce or harvest large
quantities of substances such as beer, vitamins,
amino acids, drugs, and enzymes
Industrial microbiology
involve techniques that deliberately alter the genetic makeup of organisms to mass- produce human hormones and other drugs, create totally novel substances, and develop organisms with unique methods of synthesis and adaptation.
* This is the most powerful and rapidly growing area in modern microbiology
Genetic engineering and recombinant DNA technology
5 kingdoms of organisms
the Monera or Procaryotae - bacteria
Protista – protozoa and microalgae ; nutritional modes are continuous
Fungi – yeasts and molds
Animalia, and
Plantae – green plants and higher algae
*classification scheme
domain bacteria
Unicellular prokaryotes with
cell wall containing peptidoglycan
*what are the KINGDOMS IN
Domain Archaea
prokaryotes (monera/prokaryotae)
*what are the KINGDOMS IN
Domain Eukarya
all eukaryotes
* Kingdom Animalia
* Kingdom Plantae
* Kingdom Fungi
* Kingdom Protista
Penicillin is made by the mold called
Penicillium notatum
HOW MICROORGANISMS CAUSE DISEASE (3)
Use nutrients needed by cells and
tissues
Damage cells directly
Produce toxins
Transmission of MO
Direct contact
Indirect contact
knowledge of MOs allows humans to
- Prevent disease occurrence
- Prevent food spoilage
- Led to aseptic techniques to prevent contamination in medicine and in microbiology laboratories.
concept that all living organisms are made up of cells
* they recognized that all cells from any organism are similar in structure
All living things are made up of cells.
Cells are the smallest working units of all living things.
All cells come from preexisting cells through cell division.
cell theory
-The belief that life could originate from non- living or decomposing matter
-Theory that life just “spontaneously” developed from non-living matter
Spontaneous Generation
(a.k.a Abiogenesis)
life originated from “pre existing life only”
BIOGENESIS
two different types of bacteria
a) Heat sensitive or heat labile forms (vegetative cells)
b) Heat resistant types known as an endospore
type of bacteria that is easily destroyed by boiling
Heat sensitive or heat labile forms (vegetative cells)
what theory states that infectious diseases are caused by microbes.
GERM THEORY OF DISEASE
KOCH’S POSTULATES (4)
The causative (etiological) agent must be present in all affected organisms but absent in healthy individuals
The agent must be capable of being isolated and cultured in pure form
When the cultured agent is introduced to a healthy organism, the same disease must occur
The same causative agent must be isolated again from the affected host
EXCEPTIONS TO KOCH’S POSTULATES (4)
- Microorganisms that are unable to be cultured on artificial media
- When 2 or more organism work in synergy to cause a disease.
- Symptoms or diseases that can be caused by several microbes.
- Ethical exceptions.
what do you call when Symptoms develop rapidly and tend to be more severe
Acute disease:
Disease develops slowly and are less severe
Chronic disease:
Symptoms between acute and chronic
Subacute disease:
Disease with a period of no symptoms when the causative agent is inactive
Latent disease:
Inoculation of healthy individuals with weakened (or attenuated) forms of microorganisms, that would otherwise cause disease, to provide protection, or active immunity from disease upon later exposure
VACCINATION
chicken cholera caused by
Pasteurella multocida
two types of microorganisms:
Prokaryotes
Eukaryotes(eu- good or true ; karyon – nut )
type od MO that have a relatively simple morphology and lack
a true membrane-bound nucleus
Do not have a membrane-bound nucleus
Do not have structures surrounded by membranes
Few internal structures
One-celled organisms - Bacteria
DNA is a single circular chromosome
Have both cell (plasma) membrane AND cell wall
Prokaryotes
type of MO that are morphologically complex and have a true, membrane-bound nucleus
Contain organelles surrounded by membranes
Most living organisms- fungi, algae, protozoa, animal cells, and plant cells
Cells have nuclei that contains DNA and are complex
Most cells do NOT have a cell wall
Eukaryotes
Resembles eukaryotes
Found in microorganisms that grow under extreme environmental conditions
ARCHAEBACTERIA
◆ Unicellular fungi, nonfilamentous, typically oval or spherical cells. Reproduce by binary fission, budding, or spores
e.g. Candida albicans
YEASTS
◆ Multicellular, filamentous fungi
◆ Identified by physical appearance, colony characteristics, and reproductive spores.
Molds
Possess one type of nucleic acid – either DNA or RNA
Can’t be cultivated on ordinary media
Utilize the metabolic systems or apparatus of their host
No true cellular organization
Some are enclosed by an envelope
Some have spikes
Most infect only specific types of cells in one host
Host range is determined by specific host attachment sites and cellular factors
- infect all major groups of
organisms:
- vertebrates
- Invertebrates
- plants
- fungi
- bacteria
Viruses
(Latin virus, poison or venom)
Plant Viruses
are infectious RNA molecules ; potato spindle tuber disease
Plant viruses enter through wounds or via insects
Viroids
are “infectious proteins”
They are normal body proteins that get converted into an alternate configuration by contact with other prion proteins
They have no DNA or RNA
“PrP” main protein involved in human and mammalian prion diseases
PRIONS
