1. The Cell All Living things are composed of cells
All Cells have/contain the following:
Cell Membrane - Lipid Bilayer - Separates inside from outside

2. Cytoplasm
Cytoplasm - everything but DNA/Nucleus

3. Two Cell types · Prokaryotic Cells
1.      Primitive cells – include bacteria
2.     No nucleus
3.     No Membrane-bound organelles
4.     Very Small 1-10 micrometers
5.     Single Strand of Circular “naked” DNA
6.     Contain Ribosomes

4. Typical Prokaryotic Cell

5. All Your Base Are Belong To Us

6. Eukaryotic Cells Eukaryotic Cells
1.      Contain a Nucleus which protects DNA / Chromosomes
2.     Much larger than prokaryotic cells
3.     Have many different types of Membrane bound organelles - compartmentalization = efficiency

7. Animal Eukaryotic Cell
Eukaryotic Cells
Animal Eukaryotic Cell
Plant Eukaryotic Cell

8. Organelles Membrane-Bound organelles only found in Eukaryotes
Localize Chemical Reactions making the cell far more efficient

9. Major Organelles of the Eukaryotic Cell
The Nucleus
“eukaryotic” means “true nucleus”
Contains & protects the cell’s DNA
Helps coordinate the division of cells
Surrounded by a Nuclear Envelope
Envelope is double layered with an Inner & Outer membrane
Has perforations called Nuclear Pores which allow large molecules to pass in/out of the nucleus
Contains a Nucleolus
Ribosomes are made in this region
Contains DNA packaged in structures called chromosomes
Chromosomes

10. Mitochondria
Serves as the “powerhouse of the cell” by generating chemical energy
Has it’s own DNA*
Can divide on its own*

11. Chloroplasts (Plant Cell Only)
Is the “cell’s farm” - meaning food is generated here.
Does this by photosynthesis - the conversion of CO2, H2O and sunlight into sugar
Contain Chlorophyll - a green pigment - which does this
Has it’s own DNA*
Can divide on its own*

12. Ribosomes Are NOT membrane-bound & also exist in prokaryotes
Are used to manufacture proteins
Granular in appearance
Often found on “rough” endoplasmic reticulum*

13. Endoplasmic Reticulum
Are folds of membranes used to package & modify proteins made by ribosomes. They also make lipids
2 types
“Rough” - which is usually near nucleus and covered with ribosomes giving it its “rough” appearance. (Finishes proteins)
“Smooth” - which is usually away from the nucleus (produce lipids)

14. Examples of Endoplasmic Reticulum
Smooth ER
Rough ER

15. Golgi Bodies Are the post offices of the cell
Modify (address) proteins & lipids and send them in packages (vessicles) throughout (or out of) the cell.

16. Lysosomes
Small Vessicles which serve to digest particles and clean-up cells
Contain Lysozyme – a powerful digestive enzyme
Digests food particles
Destroys worn-out organelles
Self-Destructs worn-out cells

17. Centrioles (Animal Cell Only)
Serve as construction/organization points for cellular microtubules
Organize and transfer chromosomes and other organelles during Meiosis & Mitosis
Occur in some prokaryotes, protists & animals. Do not occur with fungi and plants
Tube like structures usually at right angles to each other.
Some animals have centriole-like structures at the base of flagella called basal bodies.

18. Tonoplast (water vacuole) (plant cells only)
Large H2O / Lipid / waste storage tank
Provides pressure (Turgor pressure) to maintain cell structure

19. Cell Wall Provides support / protection for plant cell
Two layers of cell wall
Primary Cell Wall – Outer – Cellulose only
Secondary Cell Wall – Inner – Cellulose & Lignin
Cell membrane is innermost layer

20. Network of fibers which help organize the internal arrangement within cells.
Three basic types of fibers compose cytoskeleton:
Actin Filaments
Thinnest fibers ~7nM
Formed from protein Actin
Microtubules
Largest component of cytoskeleton ~25 nM
Formed from protein Tubulin
Intermediate filaments
Intermediate in size and can vary
Form from several proteins inluding vimentin & keratin
Cytoskeleton