SUMMARY 3.1

EARLY STUDIES OF CELLS

• Most cells are to small to see without the aid of a microscope
• A compound microscope contains two or more lenses

DISCOVERY OF CELLS

• In 1665, english scientist Robert Hook used
• A 3 lens compound microscope to examine thin
• Slices of cork. His observation was that cork was made of tiny hole
• Compartments

CELL THEORY

• In 1838 Mathias Schleiden proposed that plants are made of cells
• In 1839 he concluded that all living things are made of cells and cell parts
• The Major principles of the cell theory are:
• All organisms are made of cells and cells are the most basic unit of life
• All existing cells are produced by other living cells

CELL TYPES

• Prokaryotic cells do not have a nucleus
• Eukaryotic cells have a nucleus
• Cytoplasm contains molecular building blocks
• Organelles are located in the cytoplasm