1. The Cell
Heba Al-Tamimi 

2. Discovery of Cells
The first scientist to look at cells under a microscope was the English scientist Robert Hooke

3. Common feature in all cell:
Plasma membrane :the border of cell and function to regulate passage of materials into and out of cell
Nucleus :region contain genetic material
Cytoplasm :the components enclosed by the plasma membrane

4. Two Cell types
Prokaryotic Cells do not have an organized nucleus surrounded by an envelope and are relatively small (1-10 um)
compose two domains Eubacteria and Archaebacteria
Eukaryotic Cells are much larger and have an organized nucleus enclosed by a nuclear envelope
Eukarya forms 4 kingdoms :the animals ,plants ,protists and fungi

5. Common ancestor
Archaea
Eubacteria
Eukaryota
Protista
Kingdom Fungi
Kingdom Plant
Kingdom Animal

6. Eubacteria (Prokaryotes)

7. Three fundamental bacterial cell shapes Cocci Bacilli Spirilli
Exe 4-1
Three fundamental bacterial cell shapes
Cocci
Bacilli
Spirilli

8. bacteria in yoghurt
Exe 4-2
Yogurt is a nutrient-rich culture of lactic acid bacteria such as lactobacillus
These bacteria live on lactose (milk sugar) and converts milk to yogurt
To observe bacteria in yogurt the following procedure is employed
Place a very small amount of yogurt on slides by using tooth pick , spread yogurt by using other slide (smear)
Add one drop of methylene blue to the yogurt and place the cover slip
Observed under microscope

9. Cyanobacteria Photosynthetic prokaryotes Live in aquatic environment
Exe 4-3
Photosynthetic prokaryotes
Live in aquatic environment
E.x : Anabaena
Is filamentous organism and each filament is composed of long chains of greenish cells

10. Eukaryotic cells
The nucleus is separated from the rest of the protoplasm by a double membrane (nuclear envelope)

11. Human cheek cells (animal cell)
Exe 4-4
The lining inside your mouth is composed of many cell layers that serve to protect your body by forming a barrier

12. Human skin cells (animal cells)
Exe 4-5
Microscope

13. Onion epidermal cells
The onion is an underground ,storage structure made up of thickened modified leaves called scales.

14. Go To Work…….