1. There is a common structure that makes up all living things…cells.
Cells are the Basic unit of life.

2. The cell theory grew out of the work of many scientists and improvements in the microscope.
1665 First cells: Hooke
1674 pond water (living cells): Leeuwenhoek (invented microscope)
1838 All plants are made of cells: Schleiden
1839 All animals are made of cells: Schwann
1855 All cells come from other cells: Virchow
The findings of these scientists are summarized in the Cell Theory:
All living things are composed of cells
Cells are the basic units of structure and function for all living things
New cells are produced from existing cells.

3. Two Types of Cells: Prokaryotic and Eukaryotic Cells
Prokaryotic (before nucleus)
Small and most primitive
Unicellular
All have cell walls and cell membranes
Contain DNA, ribosomes and cytoplasm, but no nucleus or membrane bound organelles
Ex. bacteria
Bacterium
(colored SEM; magnification 8800x)

4. Two Types of Cells: Prokaryotic and Eukaryotic Cells
Eukaryote (true nucleus)
Have a true nucleus
Have membrane bound organelles
All have cell membranes
May have cell walls
Can be unicellular or multicellular
More evolved cells
Some have cilia
Ex. Plants, animals, fungi, protists (no bacteria)

5. Eukaryotic Cells: Plant cells differ from animal cells.
Can be all kinds of shapes
Contain: DNA, cytoplasm, ribosomes, cytoskeleton, cell membrane,mitochondria, golgi apparati, nucleus, nucleolus, and smooth & rough ER, centrioles, and lots of lysosomes

6. Plant cells contain:
DNA, cytoplasm, ribosomes, cytoskeleton, cell membrane,mitochondria, golgi apparati, nucleus, nucleolus, and smooth & rough ER
contain cell walls
Chloroplasts
Central vacuoles
Usually boxy or square shaped

7. Cell Components: Cell Membrane
Function: Protects cells, controls what enters and leaves the body of the cell
Composed of phospholipid bilayer, proteins and carbohydrates

8. Cell Components: cytoskeleton
Network of proteins that form long threads or fibers that crisscross the cell
Microtubules: give cell shape and movement of organelles
Intermediate filaments: cell strength
Microfilaments: enable cells to move and divide, help muscle contract and relax

9. Cell Components: cytoplasm
Fills space between the nucleus and the cell membrane
Fluid portion called cytosol and consist mostly of water

10. Cell organelles: nucleus
Function: storehouse for most of the genetic information or DNA
Composed of: DNA enclosed in a double membrane called the nuclear envelope, has pores (holes) to allow large molecules to pass between nucleus and cytoplasm
Also contains nucleolus that is where ribosomes are assembled.

11. Cell organelles: Endoplasmic Reticulum (ER)
Interconnected network of thin folded membranes
Two types:
rough- studded with ribosomes and responsible for protein assembly
Smooth responsible for lipid assembly, break down of drugs and alcohol

12. Cell organelles: Ribosomes
Function: link amino acids together to form proteins (protein synthesis), made up of proteins and RNA Some are found bound to the Rough ER, others are suspended in the cytoplasm

13. Cell organelles: Golgi Apparatus
Function: process, sort and deliver proteins
Also known as the UPS of the cell
Golgi

14. Cell organelles: Vesicles
Function: small membrane bound sacs that isolate some materials from the rest of the cytoplasm and transport them from place to place in the cell

15. Cell organelles: Vacuoles
Function: fluid filled sacs used for storage of water, food, ions and enzymes needed by the cell
Central vacuole: found only in plants, takes up most of the space inside the cell to provide strength and support of the entire plant, may also contain other substances (some toxic)

16. Cell organelles: Mitochondria
Function: supply energy to the cell, also known as power house of the cell
Responsible for cellular respiration
Unique in that it contains it’s own DNA and ribosomes

17. Cell organelles: Lysosome
Function: contain enzymes that are used to defend the cell from invading viruses and bacteria, break down damaged or worn out cell parts
Found in large numbers in animal cells
Also known as the cleanup crew

18. Cell organelles: Centrioles / Centrosomes
Function: organize microtubules to form cilia and flagella (used by cells for movement)
Also used in cell division in animal cells, forming spindles
Cilia-small hair-like projections that are used for movement and feeding
Flagellum (-a) long whip-like structure that is used for movement

19. Cell organelles: Cell wall
Function: rigid wall found outside of the cell membrane in plants, algae, fungi and most bacteria
Used to protect, support and shape the cell
Composition varies based on organism and it’s individual needs.

20. Cell organelles: Chloroplast
Function: carry out photosynthesis in plants, algae and bacteria
Contains chlorophyll that gives plants their green color
Has it’s own DNA and ribosomes

21. Cell Transport: Cell membrane
Cell membrane is composed of :
Phospholipid bilayer: made up of 2 rows of phospholipids, heads (hydrophilic- like water) outside and tails (hydrophobic-water hating) on the inside
Cholesterol molecules that provide strength to the cell
Proteins: act as channels, and also act as support in cytoskeleton