1. History of Cell Discovery
Chapter 4

2. Microscope view of cells
Robert Hooke – first to see cells
designed microscope that he was
able to view cork cells with (1665).
Named “Cells” because
they look like monk quarters
Cells with stone beds

3. Microscope view of cells
Anton Van Leeuwenhoek – first to see living cells.
improved design, and was
able to view red blood cells
and bacteria.
Called them "animalicules"

4. Scientists of Cell Theory
Theodore Schwann – zoologist who observed that the tissues of animals had cells (1839)

5. Scientists of Cell Theory
Mattias Schleiden – botanist who observed that the tissues of plants had cells (1845)

6. Scientists of Cell Theory
Rudolf Virchow – reported that every living thing is made up of cells, and that these cells must come from other cells.

7. Cell Theory All living things are made of one or more cells.
2. Cells are the basic unit of structure and function in organisms.
(the smallest unit that can perform life functions)
3. All cells come from pre - existing cells.

8. Terms
Cell – the smallest unit that can carry on the processes of life.
Unicellular – consists of only one cell
Multicellular – consists of more than one cell

9. Basic cell Structures Cell Membrane – outer boundary
Nucleus – control center
Cytoplasm – stuff between membrane & nucleus

10. Two Basic Cell Types
Prokaryotic – lacks internal organelles surrounded by membranes
Has a cell membrane & a cell wall
Has NO nucleus.
Means “before the nucleus”
Usually Unicellular organisms
Ex: Bacteria

11. Why should we care about prokaryotes?
Benefits prokaryotes (bacteria) provide:
Bacteria in your stomach aid in digestion
Provide immunity
Break down waste
Food production (dairy products and anything fermented)
Used in production of medicine (i.e. insulin)
You have 1 trillion cells in your body. There are 10 trillion bacterial cells living on/in your body
100 times more bacterial DNA on us or in us affecting us than our own DNA (so we're basically 99% bacteria).

12. Two Basic Cell Types
Eukaryotic – contains internal membrane bound organelles.
Has a nucleus
Has a cell membrane
Usually multicellular organisms
Ex: Plants, animals, and protists