*These discoveries lead to the cell theory* History 1) Leeuwonhoek – invents microscope 2) Hooke – uses microscope to view & name 1st cell 3) Schleiden – claims all plants are made of cells 4) Schwann – claims all animals are made of cells 5) Virchow – claims cells only come from existing cells *These discoveries lead to the cell theory*

The Cell Theory 1) All organisms are made of cells. 2) Cells are the basic unit of structure. 3) New cells come from preexisting cells.

Diversity of Cell Life All organisms fit into 2 groups: 1) unicellular- one-celled organisms 2) multicellular- many celled organism - cell specialization/differentiation - each cell has a specific function ex.- blood cells, muscle cells, nerve cells

Cell Differentiation/Specialization

Levels of Multicellular Organization 1) Cell 2) Tissue- similar cells working together 3) Organ- similar tissues working together 4) Organ System- groups of organs working together Digestive System Stomach Cell Stomach StomachTissue

Cell Types 1) Prokaryotes - no nucleus - few organelles (cell parts) - smaller, less complex ex.- Bacteria

2) Eukaryotes - have a nucleus - many organelles - larger, more complex Examples: Plant Protist Fungi Animal

CELL ORGANELLES Nucleus - controls cell’s processes - contains DNA Nucleolus - produces ribosomes within the nucleus Ribosomes - assembles amino acids into proteins Endoplasmic Reticulum - transports proteins - makes lipids for membranes

Golgi Apparatus - packages proteins for storage Lysosomes - breaks down materials for the cell Vacuoles - stores materials for the cell Mitochondria - provides energy for the cell (powerhouse) Cytoskeleton - supports the shape of the cell

Chloroplast - carries out photosynthesis (plants, algae) Cilia/Flagella - structures used for movement Cell Wall - provide extra protection (plants, fungi, bacteria)

Plant and Animal Cell Differences Plant Cell Animal Cell Contains: Cell Wall No Cell Wall Chloroplast No Chloroplast Large Vacuole Small Vacuole Shape: Square, rigid Round, fluid

Plant Cell Animal Cell