7-1 1. Cell Theory 2. Prokaryotes vs. Eukaryotes

7-1

1. Cell Theory2. Prokaryotes vs. Eukaryotes

How were cells discovered?The first cell was discovered when Robert

Hooke looked at cork under a microscope!He saw thousands of tiny empty chambers

History of the Cell

1838:Schleiden

concludes that plants are made of

cells

1665: Hooke

discovers the cell

1839: Schwann concludes that

animals are made of cells

1855:Virchow proposes that all cells come from other cells

completing the cell theory

1674: Van Leeuwenhoek observed tiny

living organisms in pond water

Cell Theory

1. All living things are made of cells.

2. A cell is the smallest unit of life.

3. All cells come from preexisting cells.

Prokaryotic Cell (bacteria)

Cell membrane

Cell membrane

Cytoplasm

Cytoplasm

Organelles

Eukaryotic Cell(plants and animals)

Prokaryote vs. Eukaryote

Nucleus

Prokaryotes

Unicellular (Single celled) No nucleus- DNA is located in the

cytoplasm in a simple circle

www.blobs.org/science/cells/prokaryote.gif

Eukaryotes

Contain organelles Often multi-cellular DNA is found chromosomes located

inside the nucleus

These are the cells that YOU have!

Organelle

What is an organelle?A membrane bound structure that

separates cell functions Found in Eukaryotic cells“little organ”

2 Basic Cell Types

Prokaryotes Eukaryotes

Prokaryotes vs. Eukaryotes

Prokaryotes Eukaryotes

Cell membraneContain DNARibosomes

NucleusEndoplasmic

reticulumGolgi apparatus

LysosomesVacuoles

MitochondriaCytoskeleton