1. What is
LIFE??

2. Living Non-Living?

3. Organize the following into your table..
Toenail
Sun
Hair
Nerve Cell
Leaf
Fire
Tree bark
Water
Algae
Bacteria

4. What makes something alive?
Ideas?

5. 7 Characteristics of Living Organisms
Feeding
Movement
Breathing/ Respiration
Excretion
Growth
Sensitivity
Reproduction

6. Biology song

7. Where does it come from…?

8. The Big Question: ???????? Can Living things come from Non-living things??

9. What is Spontaneous Generation?
The idea that organisms originate directly from non living matter
“life from nonlife”
ABIOGENESIS: the theory that states that non-living things can be transformed into living things.
abiogenesis
(a=not, bio= life, genesis= origin)
It was common knowledge that simple organisms could come from dust, mud and food left out.

10. How Did This Happen?
Every year the Nile River flooded leaving behind nutrient rich
soil that enables people to
grow that year’s crops.
However, along with the muddy
soil, large numbers of frogs
appeared that weren’t around in
drier times.
Aristotle: Greek philosopher ( BC)

11. How Did This Happen? Conclusion:
It was perfectly obvious to the people back then that muddy soil gave rise to the frogs.

12. How Did This Happen?
In many parts of Europe, medieval farmers stored grain in barns with thatched roofs. As a roof aged it started to leak. This could lead to spoiled or moldy grain, and of course, there were lots of mice around.

13. How Did This Happen? Conclusion:
It was obvious that the mice came from the moldy grain.

14. van Helmont
Even 300 years ago, a Belgian doctor, van Helmont concluded that mice could be created from grains of wheat and a dirty shirt.

15. What was wrong with van Helmont’s experiment?
Wrong: open mouthed jar….things can get in

16. Hello, Francesco Redi
Italian Doctor most well-known for his experiment in 1668 which is regarded as a one of the first steps in refuting spontaneous generation.

17. Up to this point, science was based on observation and analysis…now, experiments were needed to test the hypothesis…
In 1668, An Italian physician,
Dr. Redi, conducted an experiment to prove that flies did not come from rotting meat. Very controversial at the time…

18. What was the experimental variable? What was the controlled variable?
What was the “active ingredient” that people believed was needed for spontaneous generation?
Controlled = access to the jar active ingredient= flies
Experimental = things grow?

19. The debate rages on…100 years later
In 1748, John Needham performed an experiment similar to Redi’s except that he wanted to study the spontaneous generation of microorganisms instead of maggots.
His experiment used 2 meat infusions which were both boiled to kill the microorganisms , then one was left open, the other was sealed with a cork. Micro-organisms grew in both flasks. Needham saw it as proof of spontaneous generation….
What do you think? What was the problem with this experiment?
Problems:
didn’t test water after boiling for microorganisms
Could have gotten in through Cork
Only work if ALL microorganisms were killed (they could multiply from just one).  Would have to test every drop of water to be sure ALL were killed and in doing so the jar may be contaminated.

20. Lazzaro Spallanzani
Lazzaro Spallanzani was an Italian naturalist who also attempted to disprove the Theory of Spontaneous Generation, almost one hundred years after Francesco Redi.
With the invention of microscopes after Redi's death, scientists were able to see tiny organisms that they could not see with the naked eye.
In the late 1700's, Lazzaro Spallanzani tried to disprove this by performing a controlled experiment with broth.

21. Spallanzani…trying to disprove Needham
Still only looking at one variable = closed vs open but what about boiled vs unboiled

22. Louis Pasteur
Louis Pasteur was a French chemist who finally disproved the Theory of Spontaneous Generation in the mid 1800's.
Louis Pasteur performed the same type of experiment as Spallanzani, except both of his flasks allowed air to enter

24. And so, 2000 years after it started the debate of abiogenesis vs
And so, 2000 years after it started the debate of abiogenesis vs. biogenesis is settled: Life comes from life, not from spontaneous generation of non-living things!!!

25. Biogenesis
Biogenesis is the process of life forms producing other life forms

26. (spontaneous generation doesn’t exist!!)
LIVING LIVING
LIVING NON - LIVING
NON-LIVING LIVING
(spontaneous generation doesn’t exist!!)

27. Passport: In Your Own Words
What is the difference between Abiogenesis and Biogenesis?
Take a minute to write out the contributions of each scientist and how each affected the Abiogenesis vs. Biogenesis debate.