development of scientific process

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Development of Scientific Process Abiogenisis to Biogenisis

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Development of Scientific Process. Abiogenisis to Biogenisis. Science vs the Churches The Gauntlet 1870. Two Factors That Helped The Development Of Science:. The first was the development of the microscope.  - PowerPoint PPT Presentation

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Page 1: Development of Scientific Process

Development of Scientific Process

Abiogenisis to Biogenisis

Page 2: Development of Scientific Process

Science vs the ChurchesThe Gauntlet 1870

Page 3: Development of Scientific Process

Two Factors That Helped The Development Of Science:

• The first was the development of the microscope.

• The second was a debate about the nature of life and whether living organisms embodied vitalism or mechanism.

Page 4: Development of Scientific Process

Philosophies of VITALISM AND MECHANISM

Thoughts from the 17th and 18th Centuries

• Vitalism

• The philosophy that living organisms are endowed with special properties that allows them to operate independently of physical laws.

• It was used to explains observations like:– maggots appearing on rotting meat; – fungi growing on wood; – rodents running out of piles of vegetation...etc.

Page 5: Development of Scientific Process

Philosophy of Vitalism

• Was called spontaneous generation or abiogenesis.– It was believed that life came from nonliving

materials that received a life force from living or formerly living material

Page 6: Development of Scientific Process

Mechanism

• The philosophy that living organisms are part of the physical world and they operate according to physical laws.

• What makes something alive is not what it is made of, but how it is put together and what activities go on within its structures

Page 7: Development of Scientific Process

"Life begets life”Biogensisis

All living organisms give rise to other living organisms through fragmentation or manufacture of reproductive cells and fusion of opposite mating types to form a new organism of the same type.

• This view states that since living organisms obey regular physical laws, then the proper compounds and conditions are required to synthesize organic molecules.

Page 8: Development of Scientific Process

Abiogenesis vs Biogenesisand

The Development Of The Scientific Method

• A result of the battle between the philosophies of vitalism and mechanism was that the arguments increasingly relied on philosophical arguments that ultimately led to the development of the Scientific Method

Page 9: Development of Scientific Process

Spontaneous GenerationAbiogenesis

• Since Aristotle (4th Century BC), it was believed that non-living objects could give rise to living organisms. – Based on observations like:• Nile flooding• Moldy grain and mice• Sewers and rats

Page 10: Development of Scientific Process

Recipe for Life

• Recipe for bees:– Kill a young bull, and bury it in an upright position

so that its horns protrude from the ground. After a month, a swarm of bees will fly out of the corpse.

Page 11: Development of Scientific Process

How to Create Mice

• Jan Baptista van Helmont’s recipe for mice:– Place a dirty shirt or some rags in an open pot or

barrel containing a few grains of wheat or some wheat bran, and in 21 days, mice will appear. There will be adult males and females present, and they will be capable of mating and reproducing more mice.

Page 12: Development of Scientific Process

Life Force

• Living things had a live force that was transferred to objects

• The live force could generate new forms of life• Most common observations were from meat,

broth etc. that people had in their homes – often associated with flies.

Page 13: Development of Scientific Process

Biogenesis

• Until the 19th Century, Spontaneous Generation was accepted

• Development of ideas and technologies brought forth the idea of Biogenesis– the process of life forms producing other life

forms, e.g. a spider lays eggs, which develop into spiders.

Page 14: Development of Scientific Process

Progression of Ideas and Innovations

• 1546 - - Hieronymus Fracastorius (France) – The first to discussion the phenomenon of

contagious infection

Page 15: Development of Scientific Process

Microscopes

• 1590 - - Hans and Zacharias Janssen – made the first compound microscope.

• 1660 - - Robert Hooke – First observed cells (cork)– Used a compound microscope that could magnify

30 - 100 X.

Page 16: Development of Scientific Process

Animalcules

• 1676 - - Anton van Leeuwenhoek – developed a microscope that could magnify over

200 X. – He was the first to observe the bacteria, protists,

and other organisms. – He called these organisms animalcules.– He was considered crazy by fellow citizens

Page 17: Development of Scientific Process

Maxine Kumin, The Microscope [the full text of from Kumin’s 1963 children’s book ]:

Anton Leeuwenhoek was DutchHe sold pincushions, cloth, and such.

The waiting townsfolk fumed and fussedAs Anton’s drygoods gathered dust.

He worked, instead of tending store,

At grinding special lenses forA microscope. Some of the things

He looked at were:

mosquitoes’ wingsthe hairs of sheep, the legs of lice,the skin of people, dogs, and mice;

ox eyes, spiders’ spinning gear,fishes’ scales, a little smear

of his own blood,and best of all,

the unknown, busy, very smallbugs that swim and bump and hop

inside a simple water drop.Impossible! Most Dutchmen said.

This Anton’s crazy in the head.We ought to ship him off to Spain.

He says he’s seen a housefly’s brain.He says the water that we drink

is full of bugs. He’s mad, we think!

They called him dumkopf, which means dope.That’s how we got the microscope.

Page 18: Development of Scientific Process

First Scientific Experiment

• 1688 - - Francesco Redi

Page 19: Development of Scientific Process

Redi Experiment

• Covered jar proved that maggots did not arise spontaneously

• Critics felt that the flies on the meat with the netting were a result of Abiogenesis

Theory still not proven

Page 20: Development of Scientific Process

Disproving Redi

• 1745 - John Needham – boiled chicken broth to kill all of the

microorganisms. Sealed the container, and waited.

– Microorganisms grew a few days later, proving to him and several others that spontaneous generation did occur

Page 21: Development of Scientific Process

Biogenesis counter experimentModified Needham's experiment

• 1750's - Lazzaro Spallanzani – chicken broth in flasks were sealed, the air drawn off

with a vacuum, then boiled. – No microorganisms grew. – spontaneous generation supporters argued that

spontaneous generation could only occur in the presence of air.

– John Needham said that Spallanzani destroyed the vital force and that this experiment proved nothing

– Spallanzani is credited with developing canning – food preservation that changed how the world ate and lived.

Page 22: Development of Scientific Process

Handwashing by Physicians

• 1847 - - Ignaz Semmelweiss - – Forced doctors to wash hands– He observed the transfer of childbed fever by

doctors that did not wash their hands.

Page 23: Development of Scientific Process

Academy of Science in Paris

• To put an end to the debate between the two factions, the acadamy offered a prize to the scientist who could finally prove (or disprove) Biogenesis.

• Louis Pasteur did this.• Task – Create a timeline (to scale) to show important

events in the debate of Abiogenesis vs Biogenesis.