Warm Up• K-W-L: Microscope

Cell Theory

• Cell theory:

1. All organisms are made up of one or more cells.

2. The cell is the basic unit of organization in organisms.

3. All cells come from cells.

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Copy the following:

Cell Theory• Write the cell theory.

ACOS 2• Objective: SWBAT define the

difference between an atom and a molecule.

Magnification

• In the 1st century the romans were the first to use glass to observe small objects.

• They had discovered looking through glass made the object look bigger.

Magnification

• Salvino D’Armate made the first eye glass in the 13th century.

• The magnification of D’Armate’s eye glass was 1X.

Magnification

• Eventually simple forms of magnification glasses were about 6x-10x magnification.

• These simple forms were mainly used to observe insects like fleas.

• These early magnifiers were called “flea glasses”.

Microscopes

• Zacharias Jansen and his father put a couple of lenses in a tube and made some important discoveries.

• Jansen invented the first compound microscope.

Microscopes

• Antonie van Leeuwenhoek is commonly known as "the Father of Microbiology", and is best known for his work on the improvement of the microscope.

• Leeuwenhoek improved the microscope by improving the quality of the lens.

• Today’s compound microscopes can magnify from 1000X-2000X magnification.

Cell Theory

• Cells weren’t discovered until the microscope was improved.

• In 1665, Robert Hooke cut a thin slice of cork and looked at it under his microscope and saw empty little boxes.

• Hooke named the boxes he saw in the cork, “cells”.

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Cell Theory• Matthias Schleiden studied plants and

concluded that all plants are made of cells.

• Theodor Schwann studied animal cells and concluded that all animals are made of cells.

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• Eventually Schleiden and Schwan combined their ideas and became convinced that all living things are made of cells.

Cell Theory• Rudolph Virchow used previous

discoveries and wrote the “Cell Theory”.

• Cell theory:

1. All organisms are made up of one or more cells.

2. The cell is the basic unit of organization in organisms.

3. All cells come from cells.

Viewing CellsViewing Cells

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