1. Cells
Lecture #1

2. Cell Biology
4/19/2019
Why Study Cell Biology?
The key to every biological problem must finally be sought in the cell, for every living organism is, or at some time has been, a cell. E.B. Wilson, 1925
G. Podgorski, Biol 1010

3. Cell Biology
4/19/2019
Cells are Us
G. Podgorski, Biol 1010

4. Cilia on a protozoan Sperm meets egg
Cell Biology
4/19/2019
Cells are Us
Cilia on a protozoan Sperm meets egg
G. Podgorski, Biol 1010

5. The Cell Theory 1. ______________________________________
________________(1500’s) was first to use the term “cell”
Schleiden (botanist) and Schwann (zoologist) (1800’s)
make individual observations about cells and form the
cell theory.
Its postulates state that:
1. ______________________________________
2. The cell is the simplest structural unit of all
living things.
3. ______________________________________
Video Clip 4:40-9:00

6. There are about ______different cell types in mammals (one of us).
Cell Biology
4/19/2019
Red and white blood cells above vessel-forming cells.
Cells are Us
A person contains about 100 trillion cells. That’s 100,000,000,000,000 or 1 x 1014 cells.
There are about ______different cell types in mammals (one of us).
nerve cell
Cells are tiny, measuring on average about cm (20 um) across. That’s about 1250 cells, “shoulder-to-shoulder” per inch.
G. Podgorski, Biol 1010

7. A Sense of Scale and Abundance – Bacteria on the Head of a Pin
Cell Biology
4/19/2019
A Sense of Scale and Abundance – Bacteria on the Head of a Pin
G. Podgorski, Biol 1010

8. Frog eggs _________& chicken egg 1000-times larger than most plant and animal cells
Note relative size of nucleated cells
Most Cells are Small
Note relative size of bacteria (~1/10 size of animal/plant cells)
Note relative size of viruses (~_________ size of animal/plant cells)

9. Surface-to-Volume Ratio
Rate of “stuff” movement across membranes can be limited by amounts of membrane: solved by ______
________________________
Surface-to-Volume Ratio