1. Cell Structure and Function
Chapter 7
Cell Structure and Function

2. Scientists 1st to see cells – Robert Hooke
- Observed cork under a microscope – named the “boxes” – cells
Anton van Leeuwenhoek – 1st to observe living cells

3. Cell Theory 1. All organisms are made of cells
- Schleiden – plants made of cells
- Schwann – animals made of cells
2. Cells are the basic unit of structure and function in all organisms.
3. All cells come from pre-existing cells. (Virchow)
- 1 exception – the first cell (from nonliving)

4. Size and Shape Size and shape vary; related to function Examples
Human skin cells – flat, irregular, small – protection
Nerve cells – long, thin, string-like – transmit info throughout body
White blood cells – can change shape to escape vessels – fight disease

5. Size is limited by surface area
As surface area increases, volume increases faster

6. Types of cells Prokaryotes No nucleus No organelles w/ a membrane
Size – 1-10 um
~ 3.5 bya
Ex. bacteria
Eukaryotes
Nucleus
Organelles w/ a membrane
Size – um
~ 1.5 bya
Ex. All other living things