1. The Cell Theory

2. WOW!!! Some Random Cell Facts
The average human being is composed of around 100 Trillion individual cells!!!
It would take as many as 50 cells to cover the area of a dot on the letter “i”
WOW!!!

3. Discovery of Cells
1665- English Scientist, Robert Hooke, discovered cells while looking at a thin slice of cork.
He described the cells as tiny boxes or a honeycomb
He thought that cells only existed in plants and fungi

4. Anton van Leuwenhoek
1673- Used a handmade microscope to observe pond scum & discovered single-celled organisms
He called them “animalcules”
He also observed blood cells from fish, birds, frogs, dogs, and humans
Therefore, it was known that cells are found in animals as well as plants

5. Year Gap???
Between the Hooke/Leuwenhoek discoveries and the mid 19th century, very little cell advancements were made.
This is probably due to the widely accepted, traditional belief in Spontaneous Generation.
Examples:
-Mice from dirty clothes/corn husks
-Maggots from rotting meat

6. 19th Century Advancement
Much doubt existed around Spontaneous Generation
Conclusively disproved by Louis Pasteur
Pasteur: Ummm, I don’t think so!!! ? = +

7. Development of Cell Theory
1838- German Botanist, Matthias Schleiden, concluded that all plant parts are made of cells
1839- German physiologist, Theodor Schwann, who was a close friend of Schleiden, stated that all animal tissues are composed of cells.

8. Development of Cell Theory
1858- Rudolf Virchow, German physician, after extensive study of cellular pathology, concluded that cells must arise from preexisting cells.

9. The Cell Theory Complete
The 3 Basic Components of the Cell Theory were now complete:
1. All organisms are composed of one or more cells. (Schleiden & Schwann)( )
2. The cell is the basic unit of life in all living things. (Schleiden & Schwann)( )
3. All cells are produced by the division of preexisting cells. (Virchow)(1858)

10. How Has The Cell Theory Been Used?
The basic discovered truths about cells, listed in the Cell Theory, are the basis for things such as:
Disease/Health/Medical Research and Cures(AIDS, Cancer, Vaccines, Cloning, Stem Cell Research, etc.)

11. Cells-basic unit of life
Levels of Organization
Atom
Molecule
Cell
Tissue
Organ
Organ System
Organism

12. Cells in our world come in two basic types
"Karyose" comes from a Greek word which means "kernel," as in a kernel of grain. We use this word root to refer to the nucleus of a cell.
Prokaryote VS Eukaryote
"Pro" means "before," and "eu" means "true"
"Prokaryotic" means "before a nucleus,"
“Eukaryotic" means "possessing a true nucleus.“
Prokaryotic cells have no nuclei,
Eukaryotic cells do have true nuclei.

13. Prokaryote cells are smaller and simpler
Commonly known as bacteria
microns in size
Single-celled(unicellular) or
Filamentous (strings of single cells)
These are prokaryote
E. coli bacteria on the head of a steel pin.

14. Prokaryote (example: E. coli)
capsule: slimy outer coating
cell wall: tougher middle layer
cell membrane: delicate inner skin
cytoplasm: inner liquid filling
DNA in one big loop
pilli: for sticking to things
flagella: for swimming
ribosomes: for building proteins

15. Prokaryote lifestyle Prokaryote Feeding unicellular: all alone
colony: forms a film
filamentous: forms a chain of cells
Prokaryote Feeding
Photosynthetic: energy from sunlight
Disease-causing: feed on living things
Decomposers: feed on dead things

16. How did organelles evolve?
many scientists theorize that eukaryotes evolved from prokaryote ancestors.
in 1981, Lynn Margulis popularized the “endosymbiont theory.”

17. Endosymbiont theory: Endo = inside Symbiont = friend
a prokaryote ancestor “eats” a smaller prokaryote
the smaller prokaryote evolves a way to avoid being digested, and lives inside its new “host” cell kind of like a pet.
Endo = inside Symbiont = friend

18. the small prokaryotes that can do photosynthesis evolve into chloroplasts, and “pay” their host with glucose.
The smaller prokaryotes that can do aerobic respiration evolve into mitochondria, and convert the glucose into energy the cell can use.
Both the host and the symbiont benefit from the relationship

19. Eukaryotes are bigger and more complicated
Have organelles-
Mini “organs” that have unique structures and functions
Located in cytoplasm
Have chromosomes
can be multicellular
include animal and plant cells

20. Organelles of Eukaryotes (Plants & Animals)
Cell Membrane
Nucleus
Nucleolus
Mitochondria
Ribosomes
Endoplasmic Reticulum
Golgi Body
Lysosomes (animals only)
Centrioles (animals only)
Cytoskeleton (animals only)
Cell Wall (plant only)
Vacuole (plant only)
Chloroplast (plant only) 20

21. Cell Structures Cell membrane Nucleus
delicate lipid and protein skin around cytoplasm
found in all cells
Nucleus
a membrane-bound sac evolved to store the cell’s chromosomes (DNA)
has pores: holes

22. Nucleolus Mitochondrion inside nucleus location of ribosome factory
made or RNA
Mitochondrion
makes the cell’s energy
the more energy the cell needs, the more mitochondria it has

23. Ribosomes build proteins from amino acids in cytoplasm
may be free-floating, or
may be attached to ER
made of RNA

24. Endoplasmic reticulum
may be rough: stores proteins made by attached ribosomes
may be smooth: builds lipids and carbohydrates

25. Golgi Complex Lysosomes takes in sacs of raw material from ER
sends out sacs containing finished cell products
Lysosomes
sacs filled with digestive enzymes
digest worn out cell parts
digest food absorbed by cell

26. Cytoskeleton Centrioles made of microtubules
found throughout cytoplasm
gives shape to cell & moves organelles around inside.
Centrioles
pair of bundled tubes
organize cell division

27. Structures found in plant cells
Cell wall
very strong
made of cellulose
protects cell from rupturing
glued to other cells next door

28. Chloroplasts Vacuole filled with chlorophyll
turn solar energy into food energy
Vacuole
huge water-filled sac
keeps cell pressurized
stores starch

29. How are plant and animal cells different?
Structure
Animal cells
Plant cells
cell membrane
Yes
yes
nucleus
nucleolus
ribosomes ER
Golgi
centrioles no
cell wall
mitochondria
cholorplasts
One big vacuole
cytoskeleton

30. Advantages of each kind of cell architecture
Prokaryotes
Eukaryotes
simple and easy to grow
can specialize
fast reproduction
multicellularity
all the same
can build large bodies