KINGDOM MONERA Chpt. 18 “Bacteria”

Kingdom Monera Commonly called bacteria All monerans are unicellular All monerans are prokaryotes Prokaryotes: Single-celled organisms surrounded by a membrane and cell wall that LACK membrane bound organelles

Prokaryote Cell

Characteristics of Monera Monera can be divided into two main groups: 1) Archaebacteria - “ancient” bacteria - live in extremely harsh conditions 2) Eubacteria - “true” bacteria

Archaebacteria (ancient) Can be divided into 4 groups: 1. Methanogens “methane producers” 2. Thermoacidophiles “heat and acid lovers” 3. Chemosynthesizers “make own chemicals” 4. Extreme Halophiles “salt lovers”

Methanogens Produce methane Live where there is no oxygen Found in intestines of many mammals Found in swamps – causes the “rotten egg” smell

Thermoacidophiles Live in extremely hot and acidic waters Often found in hot springs Ex. Yellowstone National Park

Chemosynthesizers Use inorganic compounds as source of energy (instead of sun) Inorganic = compounds containing sulfur, iron, nitrogen (not carbon!) Process called oxidation Use energy to change carbon dioxide into organic food molecules Live in harsh environments (e.g. hot sulfur vents on ocean floor)

Extreme Halophiles “salt loving” Live in water up to ten times saltier than sea water Found in places like the Dead Sea

ARCHAEBACTERIA Methanogens Thermoacidophiles Chemosynthesizers Live in oxygen free environments, produce methane (CH4). Thermoacidophiles Live in water than is very hot and acidic (pH 2 to 4), line the edges of hot springs Chemosynthesizers Make carbohydrates using inorganic compounds as energy source, live in hot sulfur vents on ocean floor Extreme Halophiles Live in extremely salty places, grow in water up to ten times saltier than the ocean

Eubacteria Divided into three groups: 1. Gram-positive Bacteria 2. Gram-negative Bacteria 3. Cyanobacteria

Gram-positive Have thick cells walls. Turn purple when put through a special series of stains called “gram-staining.” Includes a wide variety of bacteria such as those causing strep throat and tetanus (lockjaw).

Gram-negative Have an extra layer of fat outside cell wall. Appear pink after gram-staining. Includes bacteria such as E.coli and the bacteria that causes whooping cough.

Gram-positive vs. negative

Cyanobacteria Perform plant-like photosynthesis. Release oxygen. Used to be called “blue-green” algae (still commonly called that!). Toxic to animals.

EUBACTERIA Gram-positive Bacteria Gram-negative Bacteria Cyanobacteria Have thick walls made of protein-sugar complex, turn purple when stained Gram-negative Bacteria Have extra layer of lipid outside cell wall and turn pink after staining Cyanobacteria Gram-negative monerans that perform photosynthesis (like plants) and release oxygen

Classifying Bacteria 3 main shapes: 1. Bacilli (rod-shaped) 2. Cocci (sphere-shaped) 3. Spirilla (corkscrew-shaped)

Why learn about Bacteria? Some cause serious diseases: Pneumonia, tuberculosis, lyme disease, bubonic plague, food-borne illnesses Most are beneficial Intestinal bacteria (digest food and make vitamins) Break down dead organisms (decomposers) Industry: make cheese, yogurt, antibiotics

KINGDOM MONERA * ARCHAEBACTERIA EUBACTERIA * * * * * * * * * Gram-positive: * Methanogens: * Gram-negative: * Thermoacidophiles: * Cyanobacteria: * Chemosynthesizers: * Extreme Halophiles: *