The Historical Development of the Concept of Life Flashcards
(47 cards)
This hypothesis explains that life originated on another planet outside our solar system
Extraterrestrial Origin Theory
This theory presumes that the “seed” of life exists all over the universe and can be propagated through space
Panspermia
Many people believed that life was put on earth by divine forces
Divine Creation
A theory in which scientists believe that life arose on Earth from inanimate matter after Earth had cooled
Origin from Non-living Matter Theory
A theory in which scientists stated that random events probably produced stable molecules that could self-replicate
Origin from Non-Living Matter Theory
When did the rapid diversification of animals, plants, and fungi appear; origin of humans about 2 million years?
> 0.5 BYA
When did the earliest animals, first multicellular organisms, and diverse protists appear?
> 1.0 BYA
When did the first eukaryotes appear?
> 1.5 BYA
When did diverse and abundant bacteria appear?
> 2.0 BYA
When did photosynthesis begin?
> 2.5 BYA
When did bacteria diversify?
> 3.0 BYA
When did the first bacteria appear?
> 3.5 BYA
When did the oldest rocks appear?
> 4.0 BYA
When did the earth form?
> 4.5 BYA
Disproved the theory of spontaneous generation. Experimented with raw meat, maggots, and flies.
Francisco Redi
Established that microorganisms do not grow from eggs and proposed the theory of Spontaneous Generation
John Needham
Disposed the theory of spontaneous generation. His hypothesis is “Microbes move through the air and can be killed through boiling.”
Lazzaro Spallanzani
Rejected the theory of Spontaneous Generation. His hypothesis is “If cells could arise from nonliving substances, then they should appear spontaneously in sterile broth.”
Louis Pasteur
Disproved the theory of spontaneous generation. “Microbes move through the air and can be killed through boiling.”
Lazzaro Spallanzani
How old is the earth?
Earth’s age is about 4.5 billion years old.
Describe how Earth was like before.
Violent, disordered, chaotic.
the energy accumulated during the burial of heat by impacts as the planet grows through the accretion of planetesimals.
Accretional Energy
- Particles from other planets
- When planets release heat, forms particles, and creates microfossils on earth.
Accretional energy
Were announced to have been discovered in hydrothermal vent precipitates 4.28 billion years ago.
Fossils (Microfossils)
