Upload
kelley-nelson
View
2.460
Download
1
Tags:
Embed Size (px)
Citation preview
Eubacteria Archebacteria Protists Fungi Plants Animals
Cell type Prokaryotic Prokaryotic Eukaryotic Eukaryotic Eukaryotic Eukaryotic
Number of Cells
Unicellular Unicellular Mostly unicellular
Mostly multicellular
Multicellular Multicellular
Mode of nutrition
Autotroph or heterotroph
Autotroph or heterotroph
Autotroph or heterotroph
Heterotroph Autotroph Heterotroph
Chemistry of cell walls
Made Peptidoglycan
No peptidoglycan
Made of cellulose (in some).
Made of chitin.
Made of cellulose
No cell walls.
Six Kingdoms of Classification
What do we already know about bacteria? Small, unicellular Prokaryotic, no nucleus, not many organelles Independent, non-specialized First life on Earth
Kingdoms of Bacteria
1. Eubacteria
• Larger of the two kingdoms• Found in most environments• Cell wall contains carbohydrate “peptidoglycan”• Ex) E.coli – bacteria in your intestine helps with
digestion
Kingdoms of Bacteria
2. Archaebacteria• Cell wall lacks peptidoglycan.• Live extremely harsh
environments• Ex.) Methanogens -live in
animal digestive tracts (no oxygen gas).
Identifying Bacteria Bacteria can be identified by…
1. Shape and Arrangement2. Chemical nature of cell wall3. Gram staining4. How they obtain energy (food)
Shape and Arrangement 3 Shapes of Bacteria
1. Bacilli (rod)2. Cocci (sphere)3. Spirilla
Colony Arrangement 1. Staphlo (clump)2. Strepto (chain)
Typical Bacteria Cell
Cell wall and cell membrane
DNA Ribosomes
Chemical Nature of Cell Wall Eubacteria identified by make-up of their cell walls. Method called Gram staining is used. Gram Positive – “thick” cell wall of peptidoglycan,
purple Gram Negative – “thin” cell wall of peptidoglycan,
pink or red – can NOT be treated by many antibiotics
Obtaining Energy All living things need a method for obtaining …
-Energy (ATP)-Organic Compounds (Carbon)
1. Heterotrophs (cannot make own food) Chemoheterotrophs- take in food for both energy
and organic compounds.ex) Salmonella bacteria eat foods and release “toxins” cause food poisoning
Photoheterotrophs- Use sunlight for energy and obtain food for a source of organic compounds.
Obtaining Energy (cont.)2. Autotrophs (make own food)
Photoautotrophs – Use sunlight to make energy and organic compounds (glucose). These bacteria are all green (kind of like little plants). Many live on surface of ocean (cyanobacteria).
Chemoautotrophs- Do not use light. Instead, use chemicals in their environment to make food and organic compounds. Live where there is no light (ocean floor).
Few Other Characterisitcs of Bacteria… Obligate aerobes- Bacteria that require a
constant supply of oxygen. Ex.) Tuberculosis Obligate anaerobes- Bacteria that do not
require oxygen. Ex) Bacteria causes botulism Facultative anaerobes- Can survive with or
without oxygen. Can live anywhere. Ex) E.coli
Few Other Characteristics of Bacteria… How do bacteria
reproduce? Binary fission
-asexual = “clones”
-1st growth
-2nd DNA copied
-3rd splits - 2 cells
Conjugation Since binary fission results in clones, bacteria need a
way to gain variety. They do this through exchanging DNA in a process
called “conjugation.” Genetic material exchanged; allows bacteria obtain new
traits = antibiotic resistance Sometimes called “transformation.”