SLE234 Study Guide - Midterm Guide: Protozoa, Eukaryote, Phagocytosis
13 Jun 2018
School
Course
Professor
Microbiology Summary:
Biomass = Earth's living material
• Microorganisms = 50%
• Plants = 35%
• Animals = 15%
Fun Fact - 90% of cells in our body are bacterial
Microorganisms
Characteristics:
1. Mostly unicellular and microscopic
2. Metabolise - transform ingested material, release energy and excrete waste products
3. Reproduce - Biochemically synthesise more cells
4. Differentiate - Alter form or function
5. Communicate - Respond to chemical signals
6. Move - Self-propulsion
7. Evolve - Change characteristics, transmit changes to progeny
Types:
• Algae
• Fungi
• Protozoa
• Bacteria
• Blue-Green Algae
• Archaea
Three Domains:
Archaea - Oldest known domain, ancient forms of bacteria.
Bacteria - All other bacteria that are not included in the Archaea domain.
Eukarya - All eukaryotic organisms or contain membrane-bound organelles and nuclei.
find more resources at oneclass.com
find more resources at oneclass.com
Why Study Microbiology?
1. Conquest of disease
2. Food industry (We can't live without cheese)
3. Biotechnology (DNA manipulation) + Medicine (antibiotics) + Industry/Agriculture (Microbial
insecticides)
4. Natural Element Cycles (Affect fertility/structure of soil)
Bioremediation - Use of microorganisms to consume and break down environmental pollutants
History of Microbiology:
Phenomena caused by micro-organisms attributed to…
• Supreme being
• Magic
• Chemical instabilities
• Spontaneous generation (non-living can give rise to living organisms)
ALL MIGHTY PASTEUR:
• In 1862 Louis Pasteur showed us that spontaneous generation was a pile of shit and
BIOGENESIS is where it's at through his swan-neck flask experiment.
Biogenesis - Living things coming from living things
• 1865-1885 Pasteur immunised farm animals against anthrax and cholera by utilising a
weakened form of disease-causing agent
• Protected dogs against rabies using an emulsion from the dried spinal cord of a rabid rabbit
Summary: 1800's people realised that certain contagions were associated with certain diseases
KOCH:
• Blood of anthrax-infected animals were teaming with bacteria
• Showed us that only one type of bacterium is able to cause a specific disease
find more resources at oneclass.com
find more resources at oneclass.com
Measurement of Microorganisms:
• Most bacterial cells are between 0.5-1.0 micrometres in diameter
• Light microscopes can't resolve objects smaller than 0.2
Units -
Metre (m) - 10
Micrometre (µm) - 1X10^-6 m
Nanometre (nm) - 1X10^-9 m
Angstrom (A) - 1X10^-10 m
Compound Microscope - Bright-field or light microscope
• Cannot be used with wavelengths <500 nm
• Forms a bright image against a darker background
Magnification: Determined by multiplying magnifications of objective and ocular lenses
Objectives: 4X, 10X, 20X, 40X or 100X
Oculars: 10X or 15X
Focal Point (F): Point at which rays/waves meets after reflection or refraction
Focal Length (f): Distance between the centre of lens and focal point
• Shorter the focal length, the larger the object appears
• Microscope magnifies decreasing focal length
Resolution: Ability to distinguish 2 adjacent points as separate
Distance (d): Minimum distance required to obtain resolution (µm)
Inreasing Resolution…
• Increasing numerical aperture to get a shorter distance
Immersing objective lens and specimen in oil:
• NA Air =0.87, d=0.29µm
• NA Immersion Oil = 1.5, d=0.17µm
• If light passes through glass-air-glass, some rays are bent/refracted and lost. Passing through
glass-oil-glass, none are lost.
• Greater Refractive Index -> Greater aperture angle over which light can spread -> Bigger cone
of light -> Max resolution
• Immersion oil has a refractive index of 1.5, thus increases aperture angle to 90 degrees
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Biomass = earth"s living material: microorganisms = 50, plants = 35, animals = 15% Fun fact - 90% of cells in our body are bacterial. Archaea - oldest known domain, ancient forms of bacteria. Bacteria - all other bacteria that are not included in the archaea domain. Eukarya - all eukaryotic organisms or contain membrane-bound organelles and nuclei. Why study microbiology: conquest of disease, food industry (we can"t live without cheese, biotechnology (dna manipulation) + medicine (antibiotics) + industry/agriculture (microbial insecticides, natural element cycles (affect fertility/structure of soil) Bioremediation - use of microorganisms to consume and break down environmental pollutants. Spontaneous generation (non-living can give rise to living organisms) In 1862 louis pasteur showed us that spontaneous generation was a pile of shit and. Biogenesis is where it"s at through his swan-neck flask experiment. Summary: 1800"s people realised that certain contagions were associated with certain diseases. Koch: blood of anthrax-infected animals were teaming with bacteria.
