Cell Theory and All About Cells

Cell Theory States:

• All living organisms are composed of cells. They may be unicellular or multicellular.
• The cell is the basic unit of life.
• Cells arise from pre-existing cells.

Wacky History

2 Types of Cells:



Prokaryotic Cells (Bacteria)

• No nucleus only free DNA
• No membrane-bound organelle (except ribosomes)
• Unicellular organisms

Eukaryotic Cells (Plant, Animal, Fungi, Protist)

• Nucleus present
• Specialized structures that work together called organelles.
• Most are multi-cellular organisms

What do Prokaryotes and Eukaryotes have in common?....

• both are cells
• both contain a deoxyribonucleic acid
• both have a cell membrane as a protective barrier
• both have ribosomes for protein synthesis
• both have cytoplasm, a jelly-like substance inside their membrane.

A cell can be compared to a city....
each organelle functioning as a part of a whole.



Each organelle has its role in the cell....




Lets assess your knowledge....Cell Quiz Section 3.1

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