Download The Discovery of Cells

The Discovery of Cells
Biology
Fall 2016
Question
What invention revolutionized the
discovery of cells and their organelles?
The invention of the microscope made
it possible for scientists to view and
study cells.
The Cell Theory
• Cells- The basic units of all living organisms.
The Cell Theory
1. All living things are made of one or more cells.
2. Cells are the basic units of structure and function in
all living things.
3. All cells come from other cells.
Electron microscopes- Allow objects to be magnified up
to 500,000x using a beam of electrons instead of light.
Scanning electron microscope
(SEM)- can help scientists see a
cell’s 3 dimensional shape.
Transmission electron microscope
(TEM)- allows scientists to see
structures inside a cell.
Types of Microscopes
• Scanning probe microscopes- produce images by tracing surfaces of
cells or structures with a probe.
Types of Cells
All cells contain small
structures called
organelles.
Each organelle has a
specific function in the
cell.
Two major classes of
cells:
1. Prokaryotic Cell
Lacks a nucleus and
most other organelles
Example: bacteria and
archaea
Types of Cells
2. Eukaryotic Cell
• Has a nucleus surrounded by a membrane and other
membrane bound organelles
• Example: protists, fungi, plants, and animals