Chapter 4: Cells 4.1 Intro to Cells; History; Microscopes Pg. 51-53 Objective: I can explain how the cell theory came to be and identify which microscopes can best view which object by factors of 10.

Cell Theory 3 ideas All organisms made of 1 or more cells Cells arise from preexisting cells Cell = smallest, most basic living thing Things to note: Where did first cell come from? Are viruses alive? This is a theory, which means… Proven with evidence, can be disproven

Cell Theory History Anton van Leeuwenhoek Made “1st” microscope Robert Hooke Named/discovered cell Matthias Schleiden All plants made of cells Theodor Schwann All animals made of cells Robert Virchow Cells come from other cells

Visualizing cells: They’re tiny Magnification: enlarging image size versus real size  wide range of sizes! http://www.allthingsscience.com/video/42/Powers-of-Ten http://www.youtube.com/watch?v=0fKBhvDjuy0

Visualizing cells: They’re tiny Units  100 meters = 1 m 103 (1000) meters = 1 kilometer (km) 10-2 meters = 1 centimeter (cm) 10-3 meters = 1 millimeter (mm) http://htwins.net/scale2/ http://scale2.s3.amazonaws.com/scale2.swf 103 102 101 100 10-1 10-2 10-3

Visualizing cells: They’re tiny Units  100 meters = 1 m 10-6 meters = 1 micrometer (µm) = micron 10-9 meters = 1 nanometer (nm) 10-10 meters = 1 Angstrom (Å) 10-6 10-9 102 101 100 10-1 10-2 10-3 10-10

Magnification: enlarge image These two are related, but separate concepts Resolution: minimium distance two points can be apart and still see as two different points http://www.youtube.com/watch?v=0fKBhvDjuy0 http://htwins.net/scale2/ 10-6 10-9 102 101 100 10-1 10-2 10-3 10-10

Resolution Minimum distance 2 points can be apart and still see as 2 different points Higher resolution = can distinguish at smaller distances Based on wavelength of light Increase resolution with shorter wavelength

Microscopes Light microscope: uses light/lenses What about magnification & resolution? Microscopes Light microscope: uses light/lenses Compound microscope: multiple lenses Electron microscope: uses electrons Scanning (SEM): scan outside Transmission (TEM): transmit inside Color?

Other Microscopic Images http://freeyork.org/art/incredible-zoom-scanning-electron-microscope-pictures http://imgur.com/gallery/E60lc http://i.imgur.com/Z4qlvRH.gifv http://i.imgur.com/E4xbipY.gifv http://i.imgur.com/jwpmvr6.webm http://i.imgur.com/dljMs33.gifv http://i.imgur.com/VDxi2nR.gifv http://i.imgur.com/RLZ0H3q.gifv https://www.youtube.com/watch?v=oSCX78-8-q0