3.1 SUMMARY

DISCOVERY OF CELLS

• In 1665, Robert Hooke used the three-lens compound microscope to identify and name cells.
• In 1674, Leeuwenhoek made better lenses, and observed organisms in greater detail.
• In 1838, Schleidon was the first tonote that plnts are made of cells.
• In 1839, Schwann concluded that all living things are madd of cells.
• In 1855, Virchow proposed that all cells come from other cells, reproducing.

CELL THEORY

• All organisms are made of cells
• All existing cells are produced by other living cells
• The cell is the most basic unit of life
• All living things are made of cells and cell products

TYPES OF CELLS

• Cytoplasm is a jellylike substance that contains dissolved molecular building blocks- such as proteins
• Organelles are structures specialized to perform distinct processes within a cell
• Prokaryotic cells do not have a nucleus or other membrane-bound organelles
• Eukaryotic cells have a nucleus and other membrane-bound cells
• Your body is made of trillions of cells with different shapes, sizes, and functions