1. CELL THEORY 1

2. Bell Ringer 5 MINUTES
19. When a person is exposed to a pathogen for the first time, he or she may develop a rash, experience swelling, and increased temperature in the area, as well as a fever. What are these symptoms due to?
histamines being produced as the result of a general or non-specific immune response
an allergy that is making the person sick
c. white blood cells recognizing specific antigens and making antibodies
d. dirt that has also entered the body and is causing an infection 3

3. Agenda Bell Ringer (5 minutes) Introduction (10 minutes)
Notebook Input (15 minutes)
Partner Work/Independent Practice (45 minutes)
Exit Quiz (10 minutes) 4

4. Intro: Growing a new Heart from Stem Cells
But where do the cells come from that make this heart? 6

5. It would take as many as 50 cells to cover the area of a dot on the letter “i”

6. What will we cover today?
1. Scientific laws vs. theories
2. Old cell theory (spontaneous generation)
3. Discoveries on the path to current cell theory
4. Three parts of current cell theory
5. Prokaryotic vs. Eukaryotic cells
Title of your notes: Cell Theory 11

7. Laws are verified statements/descriptions of what happens in nature
A. Law vs. Theory
Laws are verified statements/descriptions of what happens in nature
An example of a scientific law is the law of gravity
Theories are explanations of phenomena (things you observe); can change or be disproven
An example of a scientific theory is the theory of evolution 11

8. A long time ago… B. Spontaneous Generation:
People, including scientists, used to think that living things could form randomly from nothing
This theory was proven false by several scientists 11

9. So how did we figure out that life comes from cells?
C. Timeline of Discoveries
(timeline will be provided in class) 11

10. Our Current Cell Theory
D. 3 Parts (tenets) of Cell Theory
1. Cells are the basic unit of life 11

11. Our Current Cell Theory
2. All living things are made of cells
Multicellular (multi - many)
Unicellular (uni - one)
HINT: IF IT HAS A CELL/CELLS, IT IS A LIVING THING. 11

12. Our Current Cell Theory
3. All cells come from pre-existing cells 11

13. Prokaryotes and Eukaryotes
-kary = nucleus
-eu- = true
-pro- = before
Prokaryotes existed before eukaryotes, because they existed before the nucleus was present.
Prokaryotes originated:
4 billion years ago
Eukaryotes originated:
1 billion year ago 11

14. Cell Theory Aerobic prokaryote
Eukaryotes are more complex cells that have organelles
According to the endosymbiotic theory, eukaryotes obtained their organelles by engulfing prokaryotes.
** Those prokaryotes could have eventually become organelles
Anaerobic eukaryote 11

15. All living things are made of CELLS15

16. Where is the DNA? Eukaryotes: Have a Nucleus
HAVE MEMBRANE BOUND ORGANELLES
Are big, complex.
DNA is found in a nucleus. 11

17. Where is the DNA? Prokaryotes:
No nucleus
NO MEMBRANE BOUND ORGANELLES
Are very small/ simple.
DNA floats in the cytoplasm (Nucleoid region)
- Prokaryotes also have plasmids: small circular DNA in the cytoplasm 11

18. Check For Understanding
First we learned about laws vs. theories
Student, what is a law?
Student, add to previous student’s answer
Student, what is a theory?
Student, build upon previous student’s answer.
Student, what are some similarities or differences between laws and theories?
Student, summarize previous answers by defining and differentiating law and theory. 11

19. Check For Understanding
Next we learned what people used to think about how life started.
Student, what did people used to think (about how life started)?
Student, what was the old theory called?
Student, how was this theory disproven? 11

20. Check For Understanding
Then we learned discoveries on the path to our current cell theory.
Student, what scientific tool was invented that played a role in those discoveries?
Student, why are cells called cells? 11

21. Check For Understanding
We then learned the three parts of the cell theory.
Student, name the first part of the cell theory.
Student, name the second part of the cell theory.
Student, name the third part of the cell theory. 11

22. Check For Understanding
Finally, we learned the differences between prokaryotic and eukaryotic cells:
What is the name of the circular DNA in prokaryotes?
What type of organelles do prokaryotes lack?
How did Eukaryotes originated? 11

23. Check For Understanding
What are the two major types of cells?
What structure is present in one type, but absent in the other?
What are some examples of eukaryotic cells?
How could you determine whether an unidentified cell was prokaryotic or eukaryotic? 11

24. Notebook Output
You are a scientist and have found a microscopic object. You think that this object could be a new life form that has never been discovered.
Here are the microscopic object’s characteristics: contains DNA and protein, comes from pre-existing microscopic objects, does not contain cells.
Using the cell theory, determine if this microscopic object is a living thing. Explain why it is alive or not in 3 sentences or more. 11

25. Group Work Instructions
Microscope Stations
Cell Theory Scenarios
Plant vs Animal Cell Game
Talk quietly with YOUR PARTNER ONLY
Stay with your partner at all times, no walking around the room
Rotate quickly to the next station when you hear the timer
If you are not doing work, you will sit down and receive a zero 11

26. Independent Work Instructions
Work silently
Stay in your seat
Raise your hand for help
Work with urgency 11

27. Practice Question
Jamie is observing three different prepared slides under a light microscope. The pictures below show what she sees.
Which of the following can Jamie offer as evidence that supports the cell theory, based on these slides?
A. All cells come from parent cells that exchange DNA.
B. All living things are composed of single cells or multiple cells.
C. All cells grow and develop until they reach a certain size, at which point they die.
D. All cells are equipped with structures that enable motion, such as pseudopods or flagella. 11

28. Exit Quiz
Work silently and independently! 11

29. Home Learning: 3D model of a Cell
You must choose whether you would prefer to build a 3D model of a Plant or an Animal cell
Research/Google the organelles that belong to the type of cell you chose
You can use any type of material you would like as long as your model is a 3D one. Yes your cell could be edible if choose to do so.
You can also make a paper 3D model, as long as you are gluing your pieces and not just drawing/coloring. 22

30. Home Learning: 3D model of a Cell
Animal
Nucleus
DNA/Chromosomes
Ribosomes
Smooth and Rough: Endoplasmatic Reticulum
Golgi aparatus
Lysosomes
Cell membrane
Vacule
Mitochondria
Cytoplasm
Plant
Nucleus
DNA/Chromosomes
Ribosomes
Smooth and Rough: Endoplasmatic Reticulum
Golgi aparatus
Lysosomes
Cell Wall
Central Vacule
Mitochondria
Cytoplasm 22