An Overview of Cell Theory & Structure SBI 3C A Theory is Born… An Overview of Cell Theory & Structure
A Theory is Born… An Overview of Cell Theory and Structure (Set up your paper like this!) 1500 1600 1700 1800 1900
A Theory is Born… Ancient Times – Aristotle's “theory of spontaneous generation” 1590 – invention of microscope (Janssen)
A Theory is Born… 1665 – first sketch of “cells” (Hooke)
A Theory is Born… 1668 – Redi’s controlled experiment shows that maggots do not “appear” in meat unless flies can land on it
A Theory is Born… Microscopes continue to improve… eventually to light microscopes 1825 – “every cell is derived from a pre- existing cell” (Raspail) 1839 – “All living things are composed of cells and cell products” (Schwann)
A Theory is Born… 1845 – “Cell is the basic unit of life” (Braun) 1858 – “Where a cell exists, there must have been a preexisting cell” (Virchow) 1860 – Louis Pasteur disproves “theory of spontaneous generation”
A Theory is Born… Cell Theory: All living things are composed of one or more cells Cells are the basic units of structure and function in all organisms All cells come from pre-existing cells The activity of an entire organism depends on the total activity of its independent cells
A Theory is Born… How much do you remember ??? The End!!!