Cell Theory

Section 3.1

Vocab and Main Concept

• Cell Theory (p. 71) – Very important concept!– Know all parts

• Cytoplasm (p. 71)• Organelle (p. 72)• Prokaryotic cell (p. 72)• Eukaryotic cell (p. 72)

A Neuron

Scalded SkinCell

Myocardial cells through a light microscope

Red Blood Cells, normal and sickle cell

Chagas Disease

White Blood Cell

Cell Theory

• The cell theory grew out of the work of many scientists and improvements in the microscope.

• These are some of the names associated with the development of Cell Theory.

Cell Theory – First Telescope

This is the first compound microscope, credited to Zacharias Jansen, a teenager at the time. Some give an assist to Hans, his father.

The development of the microscope opened our minds to a world that until then, was unimagined. We suddenly were seeing strange, living, things in our water, our food, and throughout our environment.

The microscope’s invention was in 1590 and could have been given to a number of men – including the inventor of the telescope (Hans Lipershey). At the time, Holland was the center of science.

Cell Theory – Antony van Leeuwenhoek

• He discovered bacteria, free-living and parasitic microscopic protists, sperm cells, blood cells, microscopic nematodes and rotifers, and much more.– http://www.ucmp.berkeley.edu/history/leeuwenh

oek.html

Leeuwenhoek even wrote a paper about his observations on the plaque between his own teeth. Began by grinding lenses for his own microscope.

Cell Theory – The Basics

• Cell theory is a unifying concept in biology – including germ theory, genetics, and evolutionary theory.

•The principles of cell theory are three fold:1. All organisms are made of cells.2. All existing cells are produced by other living

cells.3. The cell is the most basic unit of life as the atom is

the most basic unit of matter.

Cell Theory

The mitotic division of a cell

A Euglena – you can see the flagellate and choloroplasts

Two types of cells

• There are two cell types: eukaryotic cells and prokaryotic cells.

• Eukaryotic cells have a nucleus and membrane bound organelles (you are made up of eukaryotic cells).

• Prokaryotic cells do not have membrane bound organelles and have no nucleus.

DNA of Prokaryotes

• Prokaryotes are bacteria and other very simple organisms like archea.

• The DNA of prokaryotes is in a DNA ring in organism’s cytoplasm since it has no nucleus.

DNA of Eukaryotes

• The massive difference between eukaryotes and prokaryotes is the nucleus.

• The nucleus is where the DNA is – it never ever leaves the nucleus!

• Eukaryotes also have membrane bound organelles – prokaryotes do not.

Entrance/Exit Ticket

• What are the three parts to cell theory? You must commit these to memory.

DNA of Eukaryotes

cell membrane