1. Organization of Life

2. ORGANISMS- any living thing, some are single-celled organisms and some multi-celled organisms (EX: Plants, Animals, Fungi)
ORGAN SYSTEMS- a group of organs that work together to perform a major function in the body (EX: Digestive, Integumentary)
ORGAN- a structure in the body that is composed of different kinds of tissues (EX: stomach, lungs, heart)
TISSUE-a group of similar cells that work together to perform a specific function ( EX: nervous tissue/ muscle tissue)
CELL-basic unit of structure and function in living things (EX: red blood cells, skin cells, nervous cells)

3. Cell Theory All organisms are made of cells.
All cells come from other living cells.
The cell is the most basic unit of life.

4. Contributing scientists
Robert Hooke (1663):
Coined the term “cell” after observing that cork consisted of tiny chambers
Anton von Leeuwenhoek(1673):
Invented the microscope and observed tiny living things in water
Matthias Shleiden (1938):
Discovered that all plants are made of cells-this was a new idea!
Theodor Schwann (1939):
Suggested that not just plants but animals were also made of cells!
Rudolf Virchow (1865):
Discovered that cells come only from other living cells