Cell Dudes From Long Ago Antonie van Leeuwenhoek lived from 1632 to 1723 He made the best single lens microscopes in the world at that time With it he observed many kinds of cells: Algae, Bacteria, Protozoa, and other multi-celled organisms

Antonie van Leeuwenhoek wasn’t interested in fame or money. He was just very curious. This is what he said: “... my work, which I've done for a long time, was not pursued in order to gain the praise I now enjoy, but chiefly from a craving after knowledge” Antony van Leeuwenhoek. Letter of June 12, 1716

This is what Antonie van Leeuwenhoek’s Microscope looked like:

These are some of the Cells that Antonie van Leeuwenhoek Saw:

Robert Hooke was into all aspects of science – Astronomy, Physics and Biology He Lived From 1635 to 1703 Made one of the best microscopes in the world for it’s time There are no pictures of Robert Hooke. He got into a big fight with Isaac Newton, and after he died, all of his stuff disappeared Hooke’s Really Good Microscope

Robert Hooke Looked at Cork This is a Drawing that He made: He saw little compartments, and he called them “Cells” He Gave Cells Their Name

Robert Brown lived from 1773 to 1858 He was a Botanist – He studied Plants He was a guy who looked at every thing that he could under his microscope This is his Microscope:

Robert Brown was the first person to identify the Cell Nucleus These are Orchid leaves which he observed:

The next important Cell Dude is Matthais Schleiden He lived from 1804 to 1881 He went to school to become a Lawyer, but changed his career to become a Professor of Botany instead In 1838, he came up with the idea that all plants are made from cells

Schwann discovered that Animals are also made up from cells Schwann lived from 1810 until 1882 He Studied Muscle Cells, Nerve Cells and Yeast Cells Nerve Cells

Rudolf Virchow lived from 1821 until He was a really good medical doctor. He concluded that all cells come from other cells He pushed the idea that diseases usually result from problems with cells rather than from problems with other bigger parts of the body

Together, Schleiden, Schwann and Virchow are given most of the credit for coming up with the CELL THEORY which states: 1.All living things are made from cells 2.All Cells are produced from other cells 3. Cells are the basic unit of life

Electron microscopes which magnify things 100’s of thousands of times bigger allows us to identify many cell parts and jobs. 1930’s- Electron Microscopes

TEM- Transmission Electron Microscopes- focus electron beams through thinly sliced objects. Electrons that pass through are recorded on the other side of the slide. Chloroplast at 10,000x

SEM- Scanning Electron Microscopes- scatters electrons over the surface of an object. Electrons reflect into screen. Gives a 3- dimensional look. Red Cell, Platelet, White Cell at 2,000x

SEM- Fly(100x)

SEM- Steel (10,000)

Smaller parts in the cell TEM-10,000x

The two different categories of cells: Prokaryote = no nucleus (bacteria) Eukaryote = with nucleus (animal & plant)

BUT MANY SIMPLE CELLS DON’T HAVE A NUCLEUS (Prokaryote)

Some Cells have a NUCLEUS (Eukaryotes) NUCLEUS

What do Cells look like? Well, cells come in many shapes and sizes. The background to the slides is a false color image of bacteria cells

Plant Cells Have a Cell wall around the Membrane that gives them a regular shape (Like Bricks In A Wall):

Animal Cells Have No Cell wall around the Membrane they often have irregular shapes: Brain Cancer Cell Cancer cell being attacked by the immune system

One More Picture of Animal cells: Muscle Cell

Some Single Cell Organisms have many special parts that allow them to do with just one cell the same things that most other creatures do with millions of cells:

One Complex Cell That does it all:

Some single celled plants that live in the water make really cool shells

This Is A White Blood Cell Reaching Out To Grab Invading Bacteria

Cells Are Cool! Without them Nothing would be Alive All Living things are made of Cells All Cells Come From Other Cells Cells Are the Basic Unit of Life You Are Made of Trillions of Different Kinds of Special Cells That work Together to Keep you Alive