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Learn about the three shapes of bacteria, their cellular components, and their role in nature. Understand how bacteria obtain food and energy through autotrophy and heterotrophy. Discover the processes of bacterial reproduction, including binary fission, conjugation, and endospore formation. Explore the beneficial roles bacteria play in food production, environmental recycling, and clean-up.
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Bellringer There are three shapes of bacteria: Spirilla Coccus ________
Bacteria THEY ARE EVERYWHERE!!!
Bacteria • PROKARYOTES- GENETIC MATERIAL IN THEIR CELLS IS NOT CONTAINED IN A NUCLEUS • Most known prokaryotes are BACTERIA • ONE CELLED ORGANISMS • LIVE ALMOST ANYWHERE
Parts of a Bacterial Cell • Capsule • Container surrounding the cell wall
Parts of a Bacterial Cell • Cell Wall • outer covering that protects the cell • Cell Membrane • Controls what goes in and out of the cell (also called plasma membrane)
Parts of a Bacterial Cell • Cytoplasm • Gel-like material inside the cell membrane • Ribosomes • Chemical factories where proteins are produced
Parts of a Baceterial Cell • DNA • Genetic material • Contains instructions for all of the cell’s functions
Parts of a Bacterial Cell • Flagellum • Plural Flagella • Long, whip-like structure to help cell move • May have many, 1, or none • Most do not have any & are carried from place to place by: • Air • Water currents • Other objects
Cell Size • Largest • Size of a period in a sentence • Normal • Measured in micrometers- 1 millionth of a meter • Need microscope to see!!
3 Bacterial Shapes • Cocci (Coccus) • Spherical
3 Bacterial Shapes • Bacilli (Bacillus) • Rod-shaped
3 Bacterial Cell Shapes • Spirilla (Spirochetes) • Spiral Shaped
Obtaining Food & Energy • Bacteria must have: • A source of food • A way of breaking down the food to release its energy • Bacteria are both autotrophs and heterotophs
Obtaining Energy • Autotroph • Make their own food by: • Capture and use sun’s energy (like plants do) • Use energy from chemical substances in their environment to make food Examples: bacteria in pond cause the green cloudy scum in water, bacteria in hot springs use chemical energy to make food
Obtaining Energy • Heterotroph • Consume other organisms or the food other organisms make • Example: bacteria in yogurt breaks down the sugars in milk for food
Obtaining Food and Energy: Releasing Energy • Respiration • Process of breaking down food to release energy • Aerobic bacteria- use oxygen for respiration • Anaerobic bacteria- do not use oxygen for respiration - Some can’t even survive around oxygen
Bacterial Reproduction • When bacteria have: 1. Plenty of food 2. Correct temperature 3. Suitable conditions they thrive and reproduce frequently. Some can reproduce as often as every 20 minutes!!!!!!
Bacterial Reproduction • Asexual • Involves only 1 parent and produces offspring identical to the parent • Most bacteria reproduce this way- it is called BINARY FISSION • Cell duplicates the genetic material • Cell divides into 2 separate cells
Bacterial Reproduction • Sexual • Two parents combine their genetic material to produce a new organism, which differs from both parents • Sometimes occurs • Called: • CONJUGATION
Bacterial Reproduction • Conjugation • Thread-like bridge between bacteria • One transfers DNA to another • Cells separate • Bacteria has new genetic material • Divides by binary fission producing new bacteria that are genetically different from the parent cells http://www.youtube.com/watch?v=O-EdX4MaMFE http://trc.ucdavis.edu/biosci10v/bis10v/week7/bacterial_conjugation.mov
Bacterial Reproduction • Endospore Formation • Sometimes conditions are harsh for bacteria to survive • Form Endospores for survival • Endospores- small, rounded, thick-walled, restless cell that forms inside a bacterial cell • Contains cells genetic material & cytoplasm
Role of Bacteria in Nature • Most bacteria are harmless/helpful to humans • Bacteria are involved in 1. Oxygen and food production 2. Environmental recycling and cleanup 3. Health maintenance 4. Medicine production
The Role of Bacteria in Nature • Autotrophic bacteria use sun’s energy to produce food and release oxygen • First autotrophic bacteria responsible for adding oxygen to our atmosphere
The Role of Bacteria in Nature • Food Production • Bacteria help make • Cheese • Sauerkraut • Pickles • Milk and other foods goes through pasteurization- • Food is heated up to temperature that is high enough to kill harmful bacteria without changing the taste of that food • Named after Louis Pasteur
The Role of Bacteria in Nature • Environmental Recycling • Heterotrophic Decomposers • Organisms that break down large chemicals in dead organisms into small chemicals • “Natures Recyclers” • Bacteria break down leaves on ground • Nitrogen Fixing Bacteria • Live in soil and swellings on the roots of plants • Convert nitrogenous gas from air into nitrogen products plants need
The Role of Bacteria in Nature • Environmental Clean-up • Oil eating bacteria • Convert poisonous chemicals in oil into harmless substances • Used in oil spills and gas leaks
The Role of Bacteria in Nature • Health and Medicine • Bacteria in your digestive system • Digest food • Make vitamins • Compete with disease causing organisms preventing harmful bacteria
The Role of Bacteria in Nature • Medicine • 1970’s- the first medicine producing bacteria was discovered • Insulin producing bacteria for diabetics
Bacteria • What are the five ways to “kill” bacteria? • What are the three shapes of bacteria?