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Archaebacteria & Eubacteria Notes on the World’s Smallest Organisms Bacteria are Ancient! Fossil bacteria have been found dating back 3.6 billion years Bacteria have been around for 78% of Earth’s history Humans (Homo sapiens sapiens) have only been around for about 0.004% of Earth’s history So, How long is a million years? Ex. You must spend $1,000/day, how long will it take you to spend . . . 1 day $1,000 ? 2.74 years $1,000,000 ? (1 million) 2,740 years $1,000,000,000 ? (1 billion) Bacteria are Everywhere! In Lakes, streams, ponds, and puddles Near volcanic vents at the bottom of the sea (at temperatures near 480F) In the air (thousands of feet up) On your skin (@ 100,000/cm2) 9,000 feet underground between the rocks In the soil (actinomycetes is the species that gives soil it’s smell) there are billions in every gram of soil How many bacteria are there? There are more bacteria in your mouth than all the people that have ever lived! Bacteria may outweigh trees in total biomass - How is this possible? Remember they are everywhere!! If we moved all the underground bacteria to the surface of the Earth it would form a layer 5 feet thick! Characteristics of Bacteria Shapes- Round(cocci), Rod shaped (bacilli) and Spiral (spirilla) Colors- red,yellow,blue,tan,orange,violet and others Appearance- colonies of bacteria will appear as drops of color on the surface of the growing medium (agar). They look like drops of oil paint Bacteria Shapes: Examples Appearance: Examples Structure of Bacteria Bacteria have no nucleus! The hereditary material, a circle of DNA, floats freely in the cytoplasm Some bacteria have flagella (whip like hairs) these help them move In addition to a cell membrane and a cell wall some bacteria have a capsule that protects them Bacteria Structure Parts of the bacteria Flagella- whip like hair, aids in movement Capsule- outermost layer, keeps cell from drying out Cell wall- tough covering Cell membrane- controls movement of molecules in and out of cell Hereditary Material(Nucleoid region)- One big circle of DNA and little rings of DNA called plasmids Cytoplasm- watery fluid that fills cell Ribosomes- Help make proteins Fimbria- Help bacteria cling on to stuff Life Functions of Bacteria Aerobic - use oxygen (most common today) Anaerobic- does not use oxygen Magnetotactic- use the Earth’s magnetic field to stay buried in the mud(they don’t like oxygen) Heterotrophic- parasites, decomposers Autotrophic-Make their own food; either, photosynthetically or chemosynthetically How tough are bacteria? Endospores Some times, under unfavorable environmental conditions, some bacteria form endospores. An endospore occurs when a portion of the cytoplasm plus the chromosome dehydrates. The rest of the bacterial cell deteriorates. This endospore is then highly resistant to the unfavorable conditions; conditions such as high temperatures, harsh chemicals and drying out. When good conditions occur the spore then absorbs water and returns the cell to the typical stage. Example: Dr. Cano at Cal Poly has removed 20 million year old bacteria trapped in fossilized amber, put in optimal growth conditions and watched as it came back to life and started growing! The Archaebacteria are extremeophiles. They love extreme conditions. There are species that can survive in arctic ice, some deep in the Earth, others in hot springs and even some deep in the ocean at thermal vents. They are as different from the Eubacteria as the Eubacteria are from us! This is why they were put in their own kingdom. Bacteria produce the colors seen in Yellowstone hot pools Why are the bacteria so important? They are the world’s ultimate recyclers As decomposers, bacteria breakdown dead organisms returning the molecules from them to the soil so the cycle of life can continue. Bacteria: the +’s and the -’s The positives Decomposers Added 1st oxygen to atmosphere Start soil production Make vitamins Help with foods(sourdough,yogurt,cheese) Make antibiotics Base of food chain Clean up oil spills Aid mammals in digestion The negatives Some cause illness Cause tooth decay Spoil food Eat up roads and oil drilling equipment Cause body odor Bacteria Lab Differential Staining Different types of bacteria have cell walls that are structurally different In this lab, we will see how we can use this fact to help determine different types of unknown bacteria