BSC 2011L Prokaryotes & Gram Staining

What are Prokaryotes?

What are Prokaryotes?

• most abundant organisms on earth

• in every environment

• lack membrane-bound organelles

• Bacteria and Archea

What is Domain Archea?

• look like bacteria but are genetically quite diff.

• found in every environments including extreme environments

What is Domain Bacteria?

• Diverse group that inhabit every environment on earth

• Unifying feature of lacking membrane-bound organelles

• metabolically & genetically diverse

• Identified based on shape and arrangement of cells

What is this shape called?

Coccus

What is this shape called?

Coccobacillus

What is this shape called?

Vibrio

What is this shape called?

Bacillus

What is this shape called?

Spirillum

What is this shape called?

Spirochete

What are the different arrangements of cocci called?

• Coccus

• Diplococci

• Staphylococci

• Streptococci

• Sarcina

• Tetrad

What is this arrangement of cocci called?

Coccus

What is this arrangement of cocci called?

Diplococci

What is this arrangement of cocci called?

Staphylococci

What is this arrangement of cocci called?

Streptococci

What is this arrangement of cocci called?

Sarcina

What is this arrangement of cocci called?

Tetrad

What are the different arrangements of Bacilli called?

• Coccobacillus

• Bacilli

• Diplobacilli

• Palisades

• Streptobacilli

What is this arrangement of Bacilli called?

Coccobacillus

What is this arrangement of Bacilli called?

Bacilli

What is this arrangement of Bacilli called?

Diplobacilli

What is this arrangement of Bacilli called?

Palisades

What is this arrangement of Bacilli called?

Streptobacilli

What is cyanobacteria?

• Produce Oxygen via Photosynthesis

• Fix CO2 and N out of the atmosphere

• Indicators of Water quality

What are the three groups of cyanobacteria?

• Anabaena

• Merismopedia

• Oscillatoria

What is Anabaena?

• Group of Cyanobacteria

• Forms filamentous chains

• Forms heterocysts during periods of nitrogen limitation

• Found in freshwater, saltwater, hot springs, top-soil

What is Oscillatoria?

• Group of Cyanobacteria

• Found in freshwater, saltwater, hot springs, top-soil

• Named after it’s movement

• Colonies slide back and forth against each other to orient to light source

What is Merismopedia?

• Group of Cyanobacteria

• Found in a variety of aquatic habitats and freshwater sediments

• Grid like sheets

What is Rhodospirillum Rubrum?

• Gram Negative Stain

• Pink stain

• Means there is a thin cell wall with an outer membrane

What is Gram Staining?

Distinguishes bacteria into two groups based on cell wall comp

What are the three species in Gram Stain setup?

• Staphylococcus epidermidis

• Bacillus Subtilis

• Serratia Marcescens

What is cyanobacteria surrounded by?

Sheath of glycoprotein

What are heterocysts?

specialized cells w/ ability to fix nitrogen

What are akinetes?

Thick wall dormant cells specialized for survival