Plate 10 The Spectrum of Microorganisms
Cell Size ► The smallest objects visible to the unaided eye are about 0.1 mm long Amoeba Human egg Paramecium
Centimeter ► cm = centimeter ► 1 cm = 1/100 meter ► About the width of your pinky finger
Millimeter ► mm = millimeter ► 1 mm = 1/1000 meter ► About the width of a dime
Micrometer ► μm = micrometer ► Known as a “micron” ► 1 μm = 1/1,000,000 meter microns 6-10 microns Red blood cell Human hair
Nanometer ► nm = nanometer ► 1 nm = 1/1,000,000,000 meter nm 2.5 nm
Dimensional Analysis Convert 33.2 cm into m 1 m 100 cm 33.2 cm x
Dimensional Analysis Convert 33.2 cm into m 1 m 100 cm 33.2 cm x= m
You Try!
Broad Range of Microorganisms ► Can be as small as a virus 50 nm ► Can be as large as Armillaria ostoyae (the “humongous fungus”) 8.9 km 2 (2,200 acres)
“Micro”organisms ► In order for an organism to be a “microorganism”, a microscope must be used to see the details of its structure
Viruses ► Viruses are primarily made from 2 types of molecules: A protective protein coating (capsid) DNA or RNA inside
Viruses ► 3 basic virus shapes: Helical IcosahedronComplex
Viruses ► Characteristics of viruses similar to other living organisms: Can reproduce (only inside other living cells) Can evolve (mutate)
Viruses ► Diseases caused by viruses: HIV (AIDS) Influenza Chicken pox Hepatitis Small pox
Bacteria ► Bacteria are the most abundant organisms in the world, both in number and mass ► Bacteria have the greatest diversity of species ► No one knows for sure how many species there are
Bacteria ► Bacteria can be 100 to 1000 times the size of a virus
Bacteria ► 3 main shapes: Coccus (spherical) Bacillus (rod) Spirochete & spirillum (spiral)
Bacteria
Bacteria ► Roles that bacteria play: Decomposers – recycle large organic molecules and important elements (C & N) Relatively few actually cause disease Help make food and other materials
Cyanobacteria ► Prokaryotic ► Commonly called “blue-green algae”, but they’re more closely related to bacteria than algae ► Original producers of oxygen (O 2 ) on earth Produce O 2 more than plants!
Cyanobacteria ► In warm, nutrient-rich environments, cyanobacteria can grow very quickly ► Algal blooms can use up oxygen in water, block sunlight, and release toxins
Microscopic Algae ► Two main types: Dinoflagellates (spinning whips) Diatoms
Protozoa ► Proto (first), zoa (animals) ► “Animalcules” first seen by Anton von Leeuwenhoek ► Thought to be simplest form of animal and first to appear
Protozoa ► Amoeba – move by pseudopods (“false feet”)
Protozoa ► Flagellates – move by flagella
Protozoa ► Ciliates – move by cilia
Protozoa ► Sporozoa – no locomotion, parasitic
Protozoa ► Diseases caused by protozoa: Malaria Sleeping sickness Giardia Toxoplasma
Fungi ► Two main types: Molds – sometimes macroscopic Yeasts – single-celled
Fungi ► Hyphae – single chain of cells
Fungi ► Mycelium – mass of hyphae
Fungi ► Spore – reproductive structure Can resist most environmental damage (UV light, temperature extremes, desiccation, etc.)