Spontaneous Generation

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Spontaneous Generation

  • Spontaneous Generation

  • What is this theory?

Spontaneous Generation

Theory of Biogenesis

  • Francesco Redi 1688 placed meat in 6 wide-mouthed jars. Three were covered with a type of wide weave cloth – three jars were left open.

  • All jars turned gray and began to issue vapors, but only the meat in the uncovered jars were able to be transformed into flies. Controlled experiment. Why?

Lazzaro Spallanzani

  • Late 1700’s

  • Designed an experiment to show that tiny organisms came from other tiny organisms in the air

  • Sterilized broth in two flasks, sealed one and left the other open to the air

  • The open flask became cloudy with organisms

  • The sealed one developed no organisms

  • Showed that organisms from the air entered one flask and not the other because it was sealed

Spontaneous Generation of Life

Early Microbiology

  • 1861 - Pasteur dispells theory of “spontaneous generation”

  • 1864 - Pasteur invents pasteurization of wine. Saves the French wine industry.

The Origin of Life

  • In the 1930s, a Russian scientist, Alexander Oparin, hypothesized that life began in the oceans on early earth between 3.9 to 3.5 billion years ago.

  • He suggested that first, simple organic molecules containing carbon formed. Energy from the sun, lightning, and earth's heat triggered chemical reactions to produce small organic molecules from substances present in the atmosphere.

  • These molecules were organized by chance into complex organic molecules such as proteins, carbohydrates, and nucleic acids that are essential to life.

The Formation of Amino Acids – Miller's Experiment

  • Attempting to prove Oparin's hypothesis, two American scientists, Stanley Miller and Harold Urey, carried out an experiment in which they attempted to simulate early earth conditions according to evolutionists.

  • They mixed water vapor with ammonia, methane, and hydrogen gases. They then sent an electric current that simulated lightning through the mixture. Then they cooled the mixture of gases, producing a liquid that simulated rain.

  • After a week, they collected the liquid in a flask and analyzed the chemicals therein. They found that three amino acids (amino acids constitute the basic elements of proteins, which are the building blocks of living cells) were created.

  • This experiment was claimed as proof for Oparin's hypothesis.

Miller and Urey’s Experiment

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