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Unit II - Microbiology. Section One. History of Microbiology. The First Microscope. Invented in late ______’s A simple microscope = like a ___________________. The discovery of microorganisms.
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Section One • History of Microbiology
The First Microscope. • Invented in late ______’s • A simple microscope = like a ___________________
The discovery of microorganisms. • ________________________________________________________________________________________________________________
What he did ? • _______________ and made microscopes. • First to __________________________________________________________________ • Called the little organisms “___________________”.
Basic kinds of bacteria as observed by ____________ • ___________ • spiral-shape • __________ • Spherical shape
______________ Generation • Belief that organisms arose from ______________ • Disproved by use of ________________ experiments • Louis _________– the _____________ flask
Who is this? ____________
Schwann’s flame Schulze acid base Schroeder’s cotton plug Pasteur’s
________________ • Used for many years. • __________ discovered microbes were responsible
Disease • 1540’s – first theories that _________ ____________ caused disease.
Key Discoveries • ___________isolated ________ –causing microbes • _________ discovered anthrax was caused by ________ bacteria • _______ developed _____media
Koch’s postulates • A specific microbe is associated with a given disease. • That microbe can be isolated and grown. • The pure culture can be used to infect a host organism. • Microbes can be “recovered” from infected organism
________________ • Any process that develops __________________in a host to a specific disease.
___________discovered _______________ accidentally. • By using old cultures, the injected chickens remained ___________. • He injected a ________________in those chickens and again they remained healthy.
Other breakthroughs • ________and smallpox immunization • Vaccinations (from _______ = cow) • ___________ vaccines. • Anti________ • Many more !!
Today’s Microscope. • Bright field – dark objects in bright area • Compound – multiple lenses. Up to __________ x • Electron – maximum magnification because of _______ wavelengths. Up to ___________ x
The oil immersion lens. • is _______ X • Requires ______ to prevent light ______________ • Gives maximum magnification for ____________ ________ microscope.
Quiz – History of Microbiology • COMING SOON • GET READY !!!!
Section 2 • Laboratory Techniques
Microscopes • ________ microscopes – max 2000 X • _____________ microscopes – max 400,000 X
Bright-field Microscopy • Light ____________ and dark objects.
The Compound Light Microscope • Main components for directing light. • Eyepiece, objectives, stage, condenser, iris diaphragm, fine and course adjustment knobs, base, mirror, etc.
Resolving Power • Resolving Power = wavelength NA objective + NA condenser • NA = ____________ _____________ • Wavelength range is _______to 700 nm • NA for _______ ________ is about 0.85 • NA for oil-immersion ___________: 1.2 to 1.4
Whatever the resolving power, if two objects are closer together than the numerical resolving power, they appear as _________.
No doubt you have seen a sunrise and a sunset. The sky turns red, orange, yellow and even purple because the colored wavelengths of light travel farther through the air (atmosphere). When the sun is low in the sky, this long journey through the atmosphere means the colors with shorter wavelengths, like blue, have already scattered or bounced off in numerous directions. • Orange sunsets (yellow and red light waves) appear when the air is clean. Sunsets that are the most spectacular occur when red wavelengths reflect off of overhead clouds. • Spectators continue to see light in the sky long after it has turned dark on the ground. Why is this? Because night doesn't "fall". It actually rises from the ground as the sun goes farther below the horizon. • Civil twilight occurs when the sun is 6° below the horizon. This is from the time that the sun drops below the horizon until artificial lights (street or home) are needed. • Astronomical twilight occurs when the sun is 18° below the horizon. This is when there is no sunlight on the western horizon and stars can be seen. • Twilight is shorter in the tropics because the sun's path is more perpendicular to the Earth's plane and it takes less time to go from 6° to 18° below the horizon at this angle. • White nights occur in extreme northern latitudes where the evening twilight merges with the morning twilight. • http://sci.odu.edu/sci/Scire/05Edition/sunset.html
Preparation of Specimens • ______ mount - short term mount – high dry ________ • Hanging ________ – high dry lense • Stained smears – best for bacterial form - ______ _________lens
___________ Staining • Stains background and makes bacteria stand out more clearly. • _______________ stain
Staining the Bacteria (________) • Stains bacteria and not the __________ • Main stains are ____________ _______, gentian violet (crystal violet), and carbolfuchsin.
The Staining Process Three basic steps. • ___________ • ___________ • ___________
Step One – the _________ • A very ________ slide • Place very small drop of sterile water on slide • Sterilize _______. • Obtain sample on _________
Remember Bacteria are very small !! • Smear bacteria in _________
Step two – _______ the smear • Air _____the smear • Pass slide through ________ flame up to 3 times • Do not ________ the slide until all water has disappeared !!!
Step three - __________ • Cover the ________with stain for a few seconds. • Wash all the stain off the slide. • Dry using _________ paper
________ Staining • ________Stain procedure– divides bacteria into two groups. • Gram ________ – organisms that are stained purple. • Gram ________ – organisms that retain counterstain color.
_______-_______ staining – to classify those bacteria which retain stain when washed with acids or alcohol.
Growing Bacteria in the Lab • Culture and Media
Growth Requirements: • _______________ • _______________ • ________________ • _______________.
Culture: • _______________________________________________________________________________________________________
Culture media: . • are designed to provide all the essential nutrients in solution for bacterial growth
_________ Culture • Culture containing only one species of organism.
Types of Media • ___________– for pure batch cultures • ____________ – isolation of pure cultures. Agar.
Assignment: • Read online textbook section: “Culture Media for the Growth of Bacteria” Page 16 of Word document on CD
Section 3 • Survey of the Microbial World
Terminology: • Microbiology – ____________________________________________________________ • ____________– a microorganism in the Kingdom ___________. (includes most microorganisms)
____________- a cell in which the nuclear substance is not enclosed in a membrane. (includes the bacteria)
____________ – a cell that has a definitive or true nucleus (these cells make up the bodies of all non protist organisms)
__________– obligate intracellular parasitic organism that is smaller than bacteria. They can only reproduce in cells of ___________organisms.