What observations were used to develop the cell theory?.
• German botanist, Schleiden - cells compose not only the stems and roots but every part of a plant.
• German zoologist, Schwann - made same claim about animals.
• German physician, Virchow - observed that cells come only from other cells.
2. What function do organelles serve?.
• Eukaryotic cells possess organelles.
• Their small, specific membrane-bound internal compartments, that carry out specific functions in the cell.
3. Explain why cells must be small.
• 2 limits that affect how efficiently cells work and that govern cell size.
• One is related to the exchange between the inside and the outside of the cell.
- All info and materials entering or leaving the cell must pass through .
"doors" in the cell membrane. The efficiency of this exchange depends on the ratio of the cell's surface area to its volume.
- Large cells have far less membrane surface per unit of volume with which .
to supply materials to the cells interior and to rid it of wastes.
• The other reason is that as the cell size increases, it takes longer for information and materials to reach their destination.
• SMALL CELLS ARE MORE EFFICIENT THAN LARGER CELLS.
4. Explain prokaryotes and eukaryotes.
• Prokaryotic cells are single-celled organisms that lack internal membrane-bound compartments.
• Eukaryotic cells are complex cells that have a nucleus and organelles,.
• Bacteria is the only prokaryote, all other living cells are eukaryotes.
• Many biologists think that eukaryotes evolved from prokaryotes.
5. The three parts of the cell theory.
• All living things are composed of one or more cells.
• In organisms, cells are the basic units of structure and function.