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. All living things are made of one or more cells. Cells are the basic units of structure and function in all living things. 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: Prokaryotic Cell Lacks a nucleus and most other organelles Example: bacteria and archaea

Types of Cells Eukaryotic Cell Has a nucleus surrounded by a membrane and other membrane bound organelles Example: protists, fungi, plants, and animals