1. Prokaryotes Lack a true nucleus
Unit 14
Prokaryotes
Lack a true nucleus

2. Three domains of Prokaryotes
Bacteria
Human or animal disease.
Many species even play beneficial roles by producing antibiotics and food.
The soil teems with free-living bacteria that perform many essential functions
Our bodies are covered with bacteria

3. Three domains of Prokaryotes
Archaea: Life's Extremists...!
live in extreme habitats such as thermal vents or hypersaline water.
They may be extremely abundant in environments that are hostile to all other life forms.

4. Three domains of Prokaryotes
Eukaryota
Single celled eukaryotes – Euglena, Amoeba, Paramecium
Mushrooms, bread molds, water molds, yeasts
Flowering plants, gymnosperms (conifers), ferns, mosses
Animalia

5. Three basic shapes of bacteria
Prokaryotes
Three basic shapes of bacteria
Bacilli (bacillus, singular) are rod-shaped
Cocci (coccus, singular) are spherically-shaped
Spirilla (spirillus, singular) are spiral-shaped

6. Arrangements of bacteria
Prokaryotes
Arrangements of bacteria
Chains (prefix strepto-)
Clusters (prefix staphylo-)
Twos (prefix diplo-)

7. Prokaryotes
In 1884 Hans Christian Gram developed a staining procedure, Gram Staining.
The composition of the cell wall of bacteria vary among species. Due to this difference bacteria can be divided into two groups; Gram positive and Gram negative.

8. Prokaryotes
Gram positive bacteria have thick peptidoglycan cell walls and retain a purple color when stained with crystal violet.

9. Prokaryotes Gram negative bacteria have double cell walls.
These cells retain the red color when stained with safranin.