the cell theory cells - · pdf filethe cell theory united plant and animal sciences by...

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Cells"Long ago it became evident that the key to every biological problem must finally be sought in the cell; for every living organism is, or at some time, has been a cell."E.B. Wilson

2003/2004Cells: The Basic Units of Life2

The Cell Theory

The cell theory united plant and animal sciences by recognizing that the cell is the fundamental component of all living organisms, from orchids and earthworms to human beings.


But what is a cell?

An enclosurel Boundary

l Interior regionlHereditary

store


Contributors to the Cell Theory:

§ Robert Hooke (named cells)

§ Anton Van Leeuwenhoek (saw microorganisms)

§ Robert Brown (discovered the nucleus)

§ Matthias Schleiden (plants are made of cells)

§ Theodor Schwann (animals are made of cells)

§ Rudolf Virchow (cells come from cells)

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Robert Hooke 1635~1703

In 1665The first person to

see and name cells.

He examined (dead) cork bark with a primitive microscope

Saw little cubicles which he called cells (cell = room, cubicle).


Anton van Leeuwenhoek(1632~1723)

Investigated the natural world using experimental methods supported by the evidence of the senses.

He made with his own hand certain most excellent lenses…

He invented the microscope……


And saw wondrouscreatures

Spirogyra…described by Leeuwenhoek

"Passing just lately over this lake, . . . and examining this water next day, I found floating therein divers earthy particles, and some green streaks, spirally wound serpent-wise, and orderly arranged, after the manner of the copper or tin worms, which distillers use to cool their liquors as they distil over. The whole circumference of each of these streaks was about the thickness of a hair of one's head. . . all consisted of very small green globules joined together: and there were very many small green globules as well."


Robert Brown

Robert Brown reported the existence of nucleus in 1831.

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Matthias Jacob Schleiden(solicitor & botanist 1804 ~ 1881).

Founder of the cell theory.Plants were aggregates of "fully

individualized, independent, separate being, namely the cells themselves."

Author of Basic Scientific Botany, the definitive textbook on botany at the middle of the 19th century.

Promoted commercial production of microscopes


Theodor Schwann(1810 - 1882).

Noticed nucleated units in animal tissue.

After discussions with Schleiden concluded that animals were composed of cells.

Did experiments that challenged Spontaneous Generation.


Rudolf Virchowpathologist (1858)

Omnis cellula e cellula" (where a cell arises, there a cell

must previously have existed).

First to state the cell theory:

"Every animal appears as a sum of vital units, each of which bears in itself the complete characteristics of life."


The Cell Theory

w All living things are composed of cells and cell products.

w The cell is the smallest unit of life.w Living creatures come from the

growth and division of single cells.

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Cells Come in Different Shapes


Nostoc and Amoeba and Neurons


Diatom & Mouse Hair


Cells Come in Different Sizes

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Ostrich eggs are the biggest cells.

Most cells can only be seen with a microscope.



Microscopes:

Types of MicroscopesLight Microscope

Phase~Contrast MicroscopeScanning Electron

MicroscopeTransmission Electron

Microscope


Basic Cell Types

ProkaryoticSimple StructureSmallCell MembraneCytoplasmRibosomesNO ORGANELLES

Naked DNA

Eukaryotic Complex StructureSmall to LargeCell MembraneCytoplasm Ribosomes on membranesMembrane-Bound OrganellesNucleus contains DNA

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Prokaryotic Cells

Simple Structure: Membrane, Cytoplasm, Ribosomes, and Naked DNA


Prokaryotic Cells

Archeabacteria EubacteriaCyanobacteria


More Eubacteria

Lactobacillus Nitrosomas E. coli


A Basic Eukaryotic Cell

Note the complex

inner structure

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Eukaryotic Cell

AmoebaAmorphous shape & pseudopods


Sperm and Eggs

Small Motile Cells

Large Sessile Cells


Red Blood Cells

Small cells without a nucleus. Filled with hemoglobin for oxygen transport throughout the body


Plant and Animal Cells

Cell Membrane Cell Membrane &Cell Wall

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Cell Membrane

The fluid mosaic model: Phospholipids with embedded proteins.


Cytoplasm

Cell substanceFilled with solids,liquids,

organelles, cytoskeletal support fibers & inner network of membranes.


Nucleus

The Nucleus: Control Center of the Cell2003/2004Cells: The Basic Units of Life32

Mitochondria

Cell Powerhouse: Site of Cellular RespirationC6H12O6 + O2 ? CO2 + H2O

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Endoplasmic Reticulum

Rough & Smooth Endoplasmic Reticulum

Protein Synthesis Lipid Synthesis


Golgi Apparatus

A system of sacs and vesicles in the cytoplasm


Chloroplasts

Chloroplasts : Site of PhotosynthesisCO2 + H2O ? C6H12O6 + O2


Central Vacuole

Characteristic of a Plant Cell

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Cytoskeleton

Rat Smooth Muscle Cells: Actin & Myosin


Flagella & Cilia

Trypanosome

Trypanosome Euglena Tracheal Cells


Sources

¢ http://www.ucmp.berkeley.edu/history/leeuwenhoek.html

¢ http://www.clovis.cc.nm.us/ms/adkinsj/biol113/Lectures/history_of_biology.htm

¢ http://buglady.clc.uc.edu/biology/bio104/hist_sci.htm

¢ http://www.avonmaitland.on.ca/GDCI/mains/stu-proj/science/1996/3a/cells/enrich/ryan/index.htm


§ http://members.aol.com/Poobah78/biology.html

§ http://www.nih.gov/nigms/news/science_ed/whatcell.html

§ http://biology.lsa.umich.edu/~www/bio100/lec4/index.htm§ http://www.umanitoba.ca/faculties/medicine/units/history/lesion/lesion10

.html

§ http://www.nceas.ucsb.edu/~alroy/lefa/Virchow.html

§ http://ostracon.biologie.uni-kl.de/b_online/e01/schleide.htm§ http://wwwihm.nlm.nih.gov/

§ http://www.biology.arizona.edu/cell_bio/tutorials/pev/main.html

the cell theory cells - · pdf filethe cell theory united plant and animal sciences by...

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