1. Cell Organelles!

2. Organelles
Specialized subunits of cells that have a particular function
Prokaryotes have a few (e.g., ribosomes)
Eukaryotes have many, usually surrounded by a membrane
This where we get the term “Membrane-bound organelles”

3. Cell Membrane Also called plasma membrane
Protects and supports the cell
Controls what enters and leaves the cell
It is a lipid bilayer (what does this mean??)
Found in all types of cells – prokaryotes and eukaryotes!

4. Cell Wall
Found in eukaryotic plant and protist cells; also in prokaryotes
Main function is protection, rigidity, and support
Outside of cell membrane
Made of cellulose (a carb!)
Allows water and dissolved substances to pass through.
Plant cells are surrounded by a rigid outer wall composed of cellulose.
The cell wall can also contain other components, mainly lignin.
Lignin: fills in the spaces between cellulose molecules which makes the cell wall even stronger
Major component of wood
Present in cells that make up the vascular system
Plant cells glued together by pectin

5. The Nucleus Controls most activities in the cell Usually one per cell
Contains DNA – the coded instructions for making proteins and other molecules for the cell
The nuclear envelope has nuclear pores, where things can enter or leave
Largest organelle
Usually one per cell
Typically the easiest organelle to see
Contains the DNA
Surrounded by the nuclear envelope which is a double-layered membrane containing nuclear pores
Pores allow certain substances to pass from the cytoplasm to the nucleus and vice versa.
Pores are a selective filter
See?

6. Nucleolus Small, dense region in the middle of the nucleus
This is where ribosomes are formed.
The nucleolus is located inside the nucleus.
It is not an organelle, but rather a visible region within the nucleus.
It is the site of ribosome production

7. Cytoplasm Clear fluid within cell that contains all organelles
Moves materials throughout the cell
It’s the light blue/gray stuff in this picture

8. Ribosomes Makes proteins in the cell
May be free in cytoplasm or attached to ER
Proteins are vital to life – all cells must produce them!!!
In prokaryotes and eukaryotes

9. Golgi Apparatus (Bodies)
Stacks of membranes used for storing, modifying, or packaging (the cell’s packaging plant!)
Packaged chemicals can be stored inside the cell or move outside the cell
Cells that make saliva or mucus have many Golgi bodies

10. Endoplasmic Reticulum
Series of folded membranes that form sacs or tubes
Two types – smooth and rough

11. Smooth ER vs. Rough ER Rough ER Smooth ER
Ribosomes make it look rough or bumpy
Ribosomes synthesize (make) proteins, so the Rough ER is where this happens!
Smooth ER
Smooth - no ribosomes!
Synthesizes (makes) lipids
Detoxifies drugs

12. Lysosomes Made by the Golgi Apparatus
Full of digestive enzymes to digest unwanted particles
Help white blood cells to destroy bacteria
Clean-up crew!

13. censored!!!

14. Peroxisomes Filled with enzymes to digest toxic substances
Numerous in the liver
Do not form at Golgi Body

15. Vacuoles Store food, water, or waste materials
In plant cells, they are very large!
Vacuoles and lysosomes working together! Amazing! Astounding!

16. Chloroplasts Found in eukaryotic plant cells & some protist cells
Capture light energy and convert it into chemical energy during photosynthesis

17. Mitochondria Energy producers – the “powerhouse” of the cell!
Convert chemical energy into useable energy
Found in animal and plant cells
Many mitochondria in muscle cells – why??
Contain DNA from ovum – so all your mitochondria are from your mom! (Thanks, Mom)

18. Cytoskeleton
Overlapping network of filaments and fibers that support the cell and help it maintain its shape
Can also help cells move
Microfilaments and microtubules

19. Centrioles are made of microtubules
Help to organize the cell during cell division
They migrate to either side of the cell and help to pull it apart
Only found in animal cells!
Centrioles are made of microtubules

20. Flagellum
Extension of the cytoskeleton- Allows movement, main source of transportation for cells
Only some animals and some prokaryotes have these
Has rotary engine made of proteins that spins it, very similar to a car

21. Cilia/Pili
Extension of the cytoskeleton- Allows things to move around the cell. Propels mucus in your throat, helps with hearing in your ears, and helps move food particles in your stomach.
Only some animal cells and some prokaryotes
Has rotary engine made of proteins that spins it, very similar to a car

22. Some organelles have their own DNA….
Two organelles have their own DNA – mitochondria and chloroplasts.
Among multicellular animals, nearly all of the mtDNA in a fertilized egg is inherited from only the mother.
One mechanism for this is simple dilution: an egg contains 100,000 to 1,000,000 mitochondria, whereas a sperm contains only 10 to 100.

23. Endosymbiotic Theory:
Mitochondria and chloroplasts descended from ancient prokaryotes that developed symbiotic relationships with ancient cells.
In other words… mitochondria and chloroplasts are former prokaryotes that now “live” inside eukaryotes!

24. More Historic Figures 1600s 1800s 1900s Robert Hooke – cork cells
Anton van Leeuwenhoek – “animalcules”
1800s
Matthias Schleiden – “Father of” Cell Theory
1900s
Janet Plowe –cell membrane is an actual structure
George Langford – from NC! Breakthroughs in understanding the cytoskeleton
Has rotary engine made of proteins that spins it, very similar to a car

25. The End I
Cells!