Transcript Bacteria
Bacteria AKA: Monerans Bacteria make up two of the six kingdoms currently recognized: archaebacteria and eubacteria. They come in 3 shapes: rod, sphere and spiral. Archaebacteria • “ancient bacteria” • Existed billions of years before dinosaurs, some of earth’s earliest life forms • Unicellular prokaryotes that can survive in extreme conditions (very hot or acidic) Eubacteria • Do not live in extreme conditions, but also singlecelled prokaryotes • Found EVERYWHERE, such as all over your skin and inside your mouth Reproduction in bacteria • Reproduce quickly in favorable conditions • Asexual reproduction (one parent involved) –Binary fission-genetic material duplicates and cell divides to form two identical cells • Sexual reproduction (two parents combine genetic material) –Conjugation-one bacterium transfers genetic material to another bacterial cell through a long, threadlike bridge • Cells now have new combinations of genetic material • When they divide by binary fission, new genetic material is passed and offspring are genetically different from parent • See p. 196 in your book Obtaining food… • Many move using flagella (long, whiplike tail) • Bacteria may be autotrophs or heterotrophs • Autotrophs – Photosynthesis – Energy from chemicals around them • Heterotrophs – Consuming a variety of foods – Decomposing Endospores • Formed when conditions are not favorable for growth • Small, round, thick-walled resting cell that forms inside a bacterial cell • Contains genetic material and cytoplasm • Opens up when conditions are favorable Bacteria in the Environment • Assist in production of natural gas • Used to make foods such as cheese, yogurt, soy sauce and pickles • “nature’s recyclers” • Environmental clean-up • Cause disease such as strep throat and food poisoning