Kingdom

Monera BACTERIA & BLUE-GREEN

ALGAE

C

Kingdom Monera: The ProkaryotesBACTERIA- single-celled prokaryotes- among the simplest forms of living

things- w/ few organelles or specialized

cell structures- believed to be the most abundant

organism on earth

Bacterial Structure:

FLAGELLUM- long and slender appendage; for locomotion

CELL WALL- provides rigidity, protection and identification

CAPSULE/ SLIME LAYER- contributes in protection and virulence

Bacterial Structure:

CYTOPLASMIC MEMBRANE- controls what enters and exits the cell

NUCLEAR REGION- carries genetic information

RIBOSOMES- involved in protein synthesis

Bacterial Structure:

PILI/ FIMBRIAE- shorter appendages which confer adhesive properties

MESOSOMES- large infoldings of cell membrane; increase surface area

ENDOSPORES- highly resistant body formed during extreme conditions

Bacterial Shapes

1. Bacillus – rod-shaped

2. Coccus – sphere-shaped

3. Spirillum – spiral-shaped

Staphylococcus sp.

Bacillus sp.

Spirochetes

Bacterial Reproduction:

a. Binary Fission

asexual reproduction in which

a bacterium replicates its chromosomes and divide into two

b. Budding

asexual reproduction in which an

outgrowth develops into another individual

Bacterial Reproduction:c. Spore formation/ sporulation formation of endospores which are resistant to unfavorable conditionsd. Conjugation A bacterium transfers some DNA to

another bacterium, thus changing the genes of the latter

Examples

Pathogenic bacteria

1. Streptococcus pyrogene – sore throat

2. Clostridium botulinum – paralysis due to food poisoning

3. Treponema pallidum – syphyllis

Beneficial bacteria

1. Escherichia coli – colon bacterium

2. Rhizobium sp.- nitrogen-fixing bacterium

Nutrition:A. Autotrophic – make their own food from

inorganic substances• Photosynthetic – contains chlorophyll • Chemosynthetic – make their own food

by using energy from chemical reactions involving sulfur, iron, and nitrogen

Nutrition:

B. Heterotrophic – obtain organic matter from their environment for food

• Saprophytic – feed on dead organic matter

• Parasitic – feed on other living things

Conditions for Bacterial Growth

Nutritional requirement Temperature Moisture Exposure to sunlight Chemicals

Significance of Bacteria

Food industry Medicine Leather tanning Agriculture Decomposition of living things Some can cause diseases

Some Bacterial Diseases• Rheumatic fever• Gonorrhea• Pneumonia• Meningitis• Diphtheria• Thypoid fever• Bubonic plague• Tetanus• Tuberculosis

• Anthrax• Food poisoning• Leprosy• Diarrhea• Conjunctivitis• Sore throat• Tonsillitis• Gas gangrene• Whooping cough

- spiral-shaped, w/o a rigid cell wall and move by rotating, corkscrew motion

- causes syphilis, yaws, pinta, infectious jaundice

SPIROCHAETES

- smallest known organisms that are capable of growth

& reproduction outside of living host cells

- causes primary atypical pneumonia in humans

MYCOPLASMAS/ PPLO

- obligate intracellular parasites

- cause typhus fever, Q fever, Rocky Mountain

spotted fever, Trench feverTsutsugamushi fever

RICKETTSIAE

THE ARCHAEOBACTERIA

Comparison of Viruses and Bacteria

Virus Bacterianucleus present

No No

metabolism No Yes

response to stimuli

No Yes

multiply Yes Yes

evolve Yes Yes

BLUE-GREEN ALGAE

prokaryotic unicellular: colonial or

filamentous w/ chlorophyll, phycocyanin or

phycoeryhtrin found in fresh or marine waters

& damp soil food for fish; may cause

pollution; fertilize soil

The cyanobacteria are autotrophs and obtain nutrition through photosynthesis.  They possess chlorophyll a and other pigments but lack plastids. (Remember, they are prokaryotic).  These organisms are sometimes responsible for algal blooms in polluted lakes.

                                                

Figure 3. Blue-green algae washed ashore on a small pond, 1994.

                                                                          Lyngbya colonies (blue-green algae)

                                                                                                

Large Algal Bloom

Algal Bloom Close-up

                                                                                                               

Water Sample

                                                                                                                                                                                                                                                

Aphanizomenon

                                                                                                               

                                                                     

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