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BACTERIA. Biology Chapter 24. Bacteria are very small. This is a pore in human skin and the yellow spheres are bacteria. Bacteria are very small compar-ed to cells with nuclei. Bacteria compared to a white blood cell that is going to eat it. Bacteria.
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BACTERIA Biology Chapter 24
Evolution/Classification • Most numerous on Earth • Most Ancient • Microscopic Prokaryotes • Evolution has yielded many species adapted to survive where no other organisms can. • Grouped based on: • Structure, physiology, molec. Compositionreaction to specific types of stain. • Eubacteria= Germs/bacteria • Archaebacteria
Kingdom Archaebacteria • First discovered in extreme environments • Methanogens: Harvest energy by converting H2 and CO2 into methane gas • Anaerobic, live in intestinal tracts • Extreme halophiles: Salt loving, live in Great Salt Lake, and Dead sea. • Thermoacidophiles: Live in acid environments and high temps. • Hot Springs, volcanic vents
Chemosynthetic bacteria use the sulfur in the “smoke” for energy to make ATP.
Kingdom Eubacteria • Can have one of three basic shapes • Bacilli – rod-shaped • Spirilla – spiral-shaped • Cocci – sphere-shaped • Staphylococci – grape-like clusters Streptococci – in chains SHOW ME
Diplo-bacteria occur in pairs, such as the diplococcus bacteria that causes gonorrhea
Staphylo - bacteria occur in clumps, such as this staphylococcus bacteria that causes common infections of cuts
Strepto- bacteria occur in chains of bacteria, such as this streptococcus bacteria that causes some types of sore throats
The tip of a needle The red and yellow dots are bacteria
Gram Stain • Gram-positive retain stain and appear purple • Have thicker layer in cell wall. • Gram-negative do not retain stain and take second pink stain instead.
Nutrition and Growth • Heterotrophic or Autotrophic • Some are Photoautotrophs – Use sunlight for Energy • Some are Chemoautotrophs. • Many are Obligate Anaerobes. • Oxygen = Death • Ex. Clostridium tetani – Tetanus • Some are Faculatative Anaerobes • With or without Oxygen • Ex. Escherichia Coli • Some are Obligate Aerobes • Ex.) Mycobacterium tuberculosis • Temperature requirements • Some are Thermophilic, Some prefer acidic envmt.
These heterotrophic bacteria digest oil -- remember oil is partially decayed plant and animal cells
REPRODUCTION IN BACTERIA (please add to notes)
BACTERIA REPRODUCES BY FISSION First the chromosomal DNA makes a copy The DNA replicates
NEXT THE CYTOPLASM AND CELL DIVIDES The two resulting cells are exactly the same
In addition to the large chromosomal DNA, bacteria have many small loops of DNA called Plasmids
Genetic Recombination • Nonreproductive Methods bacteria can acquire new genetic material.
TRANSFORMATION This plasmid of DNA is new to the bacteria – added by transformation! Produces the glowing protein
Some bacteria cause diseases --Disease causing bacteria are call PATHOGENIC
Helicobacter pylori is the pathogenic bacteria that can causes ulcers
Leprosy is a bacterial infection that decreases blood flow to the extremities resulting in the deterioration of toes, ears, the nose and the fingers.