1. Chapter 7: Cell Structure and Function
Cell Theory, Exploring the Cell, and Prokaryotes vs. Eukaryotes
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Created by Amy Simcik
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2. Cell theory Theodor Schwann cellS Robert Hooke prokaryotes
Bell Work
Raise your hand if you recognize the following names, terms and/or phrases….
Cell theory
Theodor Schwann
cellS
Robert Hooke
prokaryotes
Cell membrane
nucleus
eukaryotes
Electron Microscope
Rudolph Virchow
Matthias Schleiden

3. Objectives & Standards
What invention led to the formation of the cell theory?
What is the cell theory, and what evidence supports it?
How do prokaryotic and eukaryotic cells compare/contrast with each other?
How are animal and plant cells alike and different?
Standards
SOL Bio.2a –students will investigate and understand then cell theory and evidence supporting the cell theory.
SOL Bio.4a – students will investigate and understand characteristics of prokaryotic and eukaryotic cells
SOL Bio.4b – students will investigate and understand basic cell structures and functions including diversity and variation of eukaryotic cells; cell structure and function

4. Microscopes…back in the day
In the mid-1600
scientists began using an early compound microscope, like this

5. How did the invention of the magnifying lens and light microscope led to the accumulation of our knowledge of the nature of cells?
Lets find out from the
“Cell Theory Theater”

6. Take notes on your worksheet
Cell Theory Theater
Shhhhhhh! No talking please!
Take notes on your worksheet
but DO NOT interrupt the actors!

7. Image
Robert Hooke
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8. In summary…
In 1665, Robert ______ coined the term “cells” because his observations of a thin slice of ______ looked like rooms at the monastery to him under his microscope.
Hooke
cork

9. Anton van Leeuwenhoek
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10. In summary…
Anton van Leeuwenhoeke was the first to view living things in a sample of _______ water in His observations are now called ________________.
pond
micro-organisms

11. Fast Forward 164 years…

12. Matthias Schleiden
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13. In summary…
In 1838, Mathias Schleiden, a German _________, concluded that plants are composed _________.
botanist
cells

14. Theodor Schwann
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15. In summary…
In 1839, Theodor _____________, a German biologist concluded that all ________ are made of cells.
Schwann
animals

16. Rudolph Virchow
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17. In summary…
In 1855, Rudolph _______, often referred to as the “father of modern_________,” because he made many medical advances about diseases. He concluded that ____ cells could be produced only from __________cells. (Therefore the previous idea of spontaneous generation was disproved)
Virchow
pathology
new
preexisting

18. The End

19. Scientists Summary
Answer the “In conclusion…” question on your interactive notes now that summarizes the scientists’ findings.

20. The Traditional Cell Theory Tenets (beliefs):
a.) All living things are composed of one or more cells that come from other cells by the process of cell reproduction
b.) Cells are the basic units of structure and function in living things
c.) cells contain specialized structures and perform functions necessary for life

21. Microscope Advances Optical microscope Light microscope
Electron microscope
Optical microscope
Looking at passport for authenticity
Light microscope
Compound microscope
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22. Light microscope vs. Electron microscope
EMs show details that are 1000 times smaller than light microscopes can
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23. Types of Electron Microscopes
Transmission electron microscopes (TEMs)
- beams of electrons can only pass through thin samples, so cells and tissues must be cut into ultrathin slices first, then examined under the microscope.
Scanning electron microscopes (SEMs)
- pencil-like beam of electrons scanned over the specimen’s surface; 3-D images produced (no cutting) but only non-living preserved cells and tissues can be visualized
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24. 1990s – Scanning Probe Microscopes
Trace the surfaces of samples with a fine probe
Can operate in ordinary air and even show samples in a solution
Can view DNA, proteins and other biological structures.
Black/white picture
Red circles – blood cells after treatment
Green – pore of ivy leaf
Ant under SPM
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25. Thanks to microscopes…
Thanks to scientific advances in microscopes, scientists were able to study cells at a much deeper level than before.
Well then, let’s learn more about cells!

26. Thanks to microscopes…
Did you get the notes about microscopes?

27. As a result of additional study and the integration of studies of cell life functions, a Modern Cell Theory has been developed

28. energy flow (metabolism and biochemistry) occurs within cells
IN ADDITION to the traditional tenants:
energy flow (metabolism and
biochemistry) occurs within cells
cells contain hereditary information (DNA) that is passed from cell to cell during cell division
c. all cells are basically the same in chemical composition in organisms of similar species.

29. Let’s Learn About the Two Types of Cells
What is the difference between a prokaryote and a eukaryote?

30. What are Prokaryotes?
Prokaryotes are the simplest life forms exhibiting cellular structure, and were Earth’s first cells.
Two major forms
(kingdoms):
Eubacteria and
Archaebacteria
Example: Bacteria
Color-enhanced scanning electron micrograph showing Salmonella (red) invading cultured human cells
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31. Prokaryotes live in many environments
Prokaryotes are the Earth’s most abundant inhabitants. They can survive in a wide range of environments and obtain energy in a variety of ways.
Ex. Deep ocean volcano hot springs
Left to right; deep sea prokaryote; prokaryote from volcano; prokaryotes from Yellowstone National Park hot springs
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32. Prokaryotes are simple
They have no nucleus, and no membrane-bound organelles
They may have flagella or cilia for movement
As a single-celled organism, it has to conduct all life processes itself.

33. How did eukaryotes come about?
Eukaryotes arose from prokaryotes
They developed into larger, more complex organisms
Includes plants, animals, fungi & protists
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34. Prokaryotes and Eukaryotes
ALL cells have two characteristics in common: 1. surrounded by a barrier (cell membrane) 2. At some point in their lives, they contain DNA 3. contain cytoplasm and ribosomes
Two major differences:
Prokaryotes
NO nucleus; no membrane-bound organelles
Eukaryotes
Have a nucleus and membrane-bound organelles

35. Contain membrane-bound organelles
Prokaryotes
Eukaryotes
Larger & complex;
Includes plants, animals, fungi & protists
Simplest life forms
Earth’s first cells
Most abundant inhabitants
Cytoplasm
ribosomes
Cell membrane
DNA
No nucleus; no membrane-bound organelles
Great variety: single-celled to multi-cellular organisms
May have flagella or cilia for movement
Archaea = “Ar kay ah”
2 Major forms: Eubacteria
& Archaebacteria
Contain membrane-bound organelles
Ex. bacteria

36. Eukaryotic Cells
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37. Eukaryotic Cells: Plant & Animal Cells
I wonder how many differences there are between plant and animal cells?
That’s a good question because we look different, but I think we have a lot of the same parts!
But don’t forget that fungi and protists are eukaryotes too!
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38. Nuclear Envelope, Nucleus Ribosomes Endoplasmic Reticulum vacuoles
Plant
Cells
Animal
Cells
Cell membrane
Golgi Apparatus
Mitochondria
Nucleolus
Nuclear Envelope, Nucleus
Ribosomes
Endoplasmic Reticulum
Many large
vacuoles
Chloroplast
Small
vacuole
Cell Wall
Centrioles

39. Eukaryotic Cells: Plant & Animal Cells
…we have a lot of the same organelles!
Wow, we have more things in common than I thought! We might look a lot different on the outside, but when we are put under a microscope…
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41. What came first? Put items in order of their discovery
Cell theory
Invention of microscope
DNA observation
Observation of first cell

42. Scripts for Students to read during Cell Theory Theater

43. 1. Robert Hooke
Well hello there! My name is Robert Hooke. I was born in 1635 in England. Like many folk, I know what it is like to be poor; not having enough money to buy food, never mind go out and enjoy myself in the local pubs at night. As a young man I loved science! I had lots of questions about science, but without any proof, nobody would pay me for my ideas.
Due to my passion to discover and create… not that I am bragging or anything… I left behind many contributions to science from physics and astronomy, to chemistry, biology, and geology, to architecture, oh! and don’t forget about naval technology.
Some of my inventions… (pause) maybe you have heard of some… include the telescope, the early microscope, an early prototype of the respirator for breathing under water; and a balance spring found in watches and clocks. I also invented equations for laws of physics and instruments related to studying the weather, such as the barometer, sometimes on my own and sometimes with other scientists. Needless to say, by the time my inventions were finally being recognized and used by others, (smile) I did not have to worry about money any more.
To summarize a lot of my findings, I wrote a book which included some extremely detailed drawings of the flea, as you see here (point to board). One important finding was about what I saw in a piece of cork when I put it under my microscope. I saw thousands of tiny, empty chambers which looked like rooms I had seen in a monastery…you know… where monks live. Well, these rooms were called cells so I decided to use the same word to describe the small units that make up living things. Scientists after me did much more research about these ‘cells.’
(Sit down at your seat)

44. 2. Anton van Leeuwenhoeke Pronounced:“An-tony van Lay-ven-hook”
Good day! My name is Anton van Leeuwenhoeke. I was born in Holland in I began working as a tradesman, just as my parents were. They made baskets and some family members even made beer. I decided to work on making linens at first. I then decided to focus on studying science, specifically working on understanding the microscope. I made my own version of a microscope as you see here.
I was curious about what was around us that I could not see with my eye. I took a sample of pond water, used my microscope and noticed many little creatures. I called them “animal-cules.” People after me apparently did not like this name so they called them single-celled organisms, which we now call micro-organisms.
After exploring pond water I was curious about other microscopic things. I was the first to record microscopic documentation of muscle fibers, bacteria, and blood vessels. Because of my hard work and my discoveries, people called me the “Father of Microbiology.”
The study of cells did not stop here. More scientists came after me and further developed my findings.
(Sit down at your seat)

45. 3. Matthias Schleiden Pronounced “Ma-thigh-as Sch-leigh-den” Hello
3. Matthias Schleiden Pronounced “Ma-thigh-as Sch-leigh-den” Hello! My name is Matthias Schleiden, and I was born in Germany in I first studied law when I was in my twenties. After five years of being a lawyer and got bored, so I decided to switch careers and become a botanist because I loved plants! Not only did I study botany, I became a professor at a university and taught about botany. While teaching was fun, I still was curious about plants, so I did research on my own as well. I enjoyed learning new things about plants that were not yet explained or discovered. Seven years passed by and I decided to share my findings from my research with other scientists. In 1838 I concluded that the different parts of plants are composed of cells. This finding became very important in the explanation of cells, known as the cell theory. My friend, Rudolph Virchow, who you will hear from soon, also had a part in the cell theory with me. (Stand off to the side of the room. Get ready to jump in and say a line WITH Theodor Schwann when he starts to say:) “I can’t take all the credit, but in 1839, Matthias Schleiden and I developed the cell theory, where we said… (Say together) All living things are composed of cells, and cell products are reproduced. (Sit down when he finished talking)

46. 4. Theodor Schwann
Hello, and good day to all of you. My name is Theodor Schwann, and I was born in 1810 in Germany. I studied biology and also was interested in cells. Unlike my friend Matthias Schleiden (Ma-theigh-as Sch-leigh-den), I studied animal cells. I realized that animal cells had different properties than the plant cells that he was studying.
We were having dinner one fine evening when we started to discuss our work with cells and we then realized that instead of competing with each other, if we put our ideas together about plant and animal cells, our research made more sense. Both of us noticed that nuclei were in the cells we studied.
I had a particular interest in figuring out how digestion worked and discovered enzymes that ultimately are responsible for digestion. I discovered other muscle cells found in the esophagus which, not to brag, but are named after me.
Now, I can’t take all the credit, but in 1839, Matthias Schleiden and I developed the cell theory, where we said… (WAIT FOR MATTHAIS SCHLEIDEN TO STAND NEXT TO YOU, then say together) “All living things are composed of cells, and cell products are reproduced.”
(Look at the other student and say…)
Ah, thank you for reliving that moment with me Matthias!
(Look back at class) Together we both recognized that membranes, nuclei and cell bodies were common features found in animal and plant cells.
Another scientist decided to do more research and add to our findings…
(Walk back to your seat)

47. 5. Rudolph Virchow Hello there
5. Rudolph Virchow Hello there! Like many of you, I have a very long name, which is Rudolph Ludwig Karl Virchow, however I normally just go by Rudolf Virchow. I was born in 1821 in Germany. I too decided to try out many careers ranging from anthropology, pathology, history, biology and even politics. Despite my many career paths, I am best known for my advances in medicine and because of this, people decided to call me the “father of modern pathology.” If you were not sure, pathology means the study and diagnosis of disease. (Deep breath and smile) But back to my most famous discovery… I looked at the findings of Theodor Schwann and also the findings of another scientist and decided to take their research a step further. (Act like you are about to tell a secret…) Ok, so between you and me, I kind of stole my friend’s ideas and beat him to publishing the findings that said that every cell originates from another existing cell like it, (pause) but let’s keep that between you and me. Oh, and if you were wondering, we are not friends anymore after he found out what I did. What is important is that I… (little laugh) …concluded that new cells could be produced only from the division of existing cells. So, thanks to me, Theodor Schwann and Matthias Schleiden (Ma-thigh-as Sch-leigh-den), we came up with the cell theory! (Take a bow, and then take your seat)

48. Works cited: http://www. ourstory. com/thread. html. t=344670 www
Works cited: Miller & Levine Biology text