3.1 Cell Theory KEY CONCEPT Cells are the Basic unit of life.

3.1 Cell Theory The cell theory grew out of the work of many scientists and improvements in the microscope. Many scientists contributed to the cell theory.

3.1 Cell Theory More was learned about cells as microscopes improved with better images and greater magnification. The cell theory grew out of the work of many scientists and improvements in the microscope.

3.1 Cell Theory Cell Theory is a unifying concept of biology. 1.All organisms are made of cells.

3.1 Cell Theory Cell Theory is a unifying concept of biology. 1.All organisms are made of cells. 2.All existing cells are produced by other living cells.

3.1 Cell Theory Cell Theory is a unifying concept of biology. 1.All organisms are made of cells. 2.All existing cells are produced by other living cells. 3.The cell is the most basic unit of life.

3.1 Cell Theory All cells share certain characteristics. – –All cells are enclosed by a membrane. – –All cells are filled with cytoplasm. – –All cells have DNA.

3.1 Cell Theory There are two cell types: eukaryotic cells and prokaryotic cells. All animals and plants and some single-celled organisms are eukaryotic. Bacteria are prokaryotic. Bacterium (colored SEM; magnification 8800x) Eukaryote Prokaryote

3.1 Cell Theory There are two cell types: eukaryotic cells and prokaryotic cells. nucleus cell membrane organelles Eukaryotic cells have a nucleus that contains DNA. Prokaryotic cells do not have a nucleus. DNA is free-floating.

3.1 Cell Theory There are two cell types: eukaryotic cells and prokaryotic cells. nucleus cell membrane organelles Eukaryotic cells have organelles surrounded by membranes. Prokaryotic cells do not have organelles.

3.1 Cell Theory eukaryotic prokaryotic DNA nucleusorganelles cytoplasmcell membrane 1. cell membrane 2. cytoplasm 3. DNA

3.1 Cell Theory