2. Early Contributions
Robert Hooke - First person to see cells, he was looking at cork and noted that he saw "a great many boxes. (1665)
Anton van Leeuwenhoek - Observed living cells in pond water, which he called "animalcules" (1673)

3. Schwann, Schleiden, Virchow – Cell Theory
Theodore Schwann - zoologist who observed tissues of animals had cells (1839)
Mattias Schleiden - botanist, observed tissues of plants contained cells ( 1845)
Rudolf Virchow - also reported that every living thing is made of up vital units, known as cells. He predicted that cells come from other cells. (1850 )
Schwann, Schleiden, Virchow – Cell Theory

4. The cell theory 1. All living things are composed of cells.
2. Cells are the basic unit of structure and function in living things.
3. New cells are produced from existing cells.
*Why is the Cell Theory called a Theory and not a Fact?

5. Cell Features ALL cells have these parts
Ribosomes – make protein for use by the organism
Cytoplasm – fluid material within  cell
DNA – genetic material
Cytoskeleton – internal framework of cell
Cell Membrane – outer boundary, some things can cross the cell membrane

6. Comprehension Checkpoint
Answer true or false
Robert Hooke was the first person to see cells.
Bacteria cells have a cell membrane.
The Cell Theory was developed by a single scientist.
Plant cells have cytoplasm.
Cells taken from fungi do not have DNA.
Cells can only come from pre-existing cells.

7. Prokaryote Cells The first cells to inhabit the earth Simple cells
Bacteria
These cells do NOT have a nucleus, their DNA is circular and floats in the cytoplasm
Some bacteria have a tail-like structure called a flagella, that helps it to move.
A capsule surrounds some bacteria and helps them avoid the body’s immune system

8. Bacteria-prokaryotic
Bacteria that causes Anthrax

9. Eukaryotic Cells Cells found in plants, animals, protists, and fungi
The eukaryotic cell is composed of 4 main parts:
Cell membrane
Cytoplasm
Nucleus – “control center” of cell, houses DNA
Organelles – small structures that carry out specific functions (“little organs”)

10. Nucleus Usually found at center of cell
Has a nuclear membrane & nuclear pores
 Contains cell’s DNA in one of 2 forms
chromatin - DNA bound to protein (non-dividing cell)
chromosomes - condensed structures seen in a dividing cell (look like Xs)
 Also contains an organelle called nucleolus - which makes the cell’s ribosomes
Nickname: Brain or Headquarters

11. Cell Organelles Mitochondria – this is the cell’s energy center.
-Creates ATP
-ATP = Adenosine Triphosphate
-Produces energy through chemical reactions – cellular respiration
-Nickname:“powerhouse” of the cell.

12. Cell Organelles
Golgi Apparatus – processes, packages and secretes proteins.
Nickname-FedEx or Post Office of the cell
*A vesicle is used with the Golgi to transport substances outside cell, like a messenger delivering a package.  

13. Cell Organelles
Lysosome – Contains digestive enzymes, breaks things down,
Nickname: Trashcan or Pac-Man of the cell
Endoplasmic Reticulum – Nickname: Highway or Subway of the cell
-transports materials
 -Rough ER contains many ribosomes & is involved in protein synthesis
 -Smooth ER ribosomes not found on surface

14. Cell Organelles Cytoskeleton – Helps cell maintain
support & shape; movement
a. microtubules-hollow structures; also
help build cilia  flagella
b.  microfilaments-threadlike
c.  centrioles-only in animal cells; used
during cell division (paired) 
Vacuole – storage area for water and other substances, plant cells usually have a large central vacuole

15. Protein Production
The cell is like a factory. Its product is protein which goes to body to serve different functions.
DNA has instructions to build protein
These instructions are sent to ribosomes
The ribosomes build protein and send it through ER
The proteins are delivered to golgi where they are completed and “tagged” for export outside cell

16. THE ANIMAL CELL

17. Cheek Cells Seen Through Microscope

18. Plant Cells Have additional structures
CELL WALL – surrounds membrane & provides additional support
CHLOROPLASTS – contain green pigment chlorophyll, functions in photosynthesis
CENTRAL VACUOLE – large water container in center of cell

19. PLANT CELL
Can you identify the parts?

20. Anacharis Cells Viewed With a Microscope

21. Organelles With DNA
Mitochondria and chloroplasts have their own DNA (separate from the nucleus)
This supports the ENDOSYMBIOSIS THEORY which states that eukaryotic cells evolved when prokaryote cells engulfed or absorbed other cells.

22. CELL MEMBRANE
Selectively permeable; it regulates what comes into the cell and what leaves the cell
It is composed of a double layer of phospholipids with proteins embedded throughout (phospholipid
bilayer)

23. Venn Diagrams Prokaryotes Eukaryotes Animal Cells Plant Cells Nucleus
Endoplasmic reticulum
Golgi apparatus
Lysosomes
Vacuoles
Mitochondria
Cytoskeleton
Capsule
Cell membrane
Ribosomes
Cell wall
Animal Cells
Plant Cells
Cell membrane
Ribosomes
Nucleus
Endoplasmic reticulum
Golgi apparatus
Vacuoles
Mitochondria
Cytoskeleton
Cell Wall
Chloroplasts
Lysosomes
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