Unit 9 notes 1 Flashcards
Define sponstaneous generation
the idea that non - living material can produce live
What did franchisco Redi and Louis Pasteur do?
disproved sponstaneous generation
Define biogenesis
all living organisms come from only other living things
What had to occur before life could appear on earth?
- simple organic molecules (have carbon) must have formed
- these simple organic molecules must have came together to from, proteins, carbs, and nucleic acids
What was earths early atmosphere like?
- no oxygen
- had water vapor, carbon dioxide, nitrogen, and nucleic acid
What was Alexander Oparin’s hypothesis?
That life began in the oceans when energy from the sun, lightning, and Earth’s heat triggered chemical reactions that made small molecules from substances present in the atmosphere
What did Miller and Urey do?
Mixed water vapor, ammonia, methane, and hydrogen gas together in a flask, then sent an electric shock throught the flask
(recreate primordial soup)
What did Miller and Urey find when they recreated the primordial soup?
amino acids and sugars
define protocells
A structure surrounded by a membrane`
What formed protocells?
scientist believe that amino acids came together to from protocells
How long ago did fossils show that prokaryotic cells existed on earth?
fossils show that prokaryotic cells existed on earth 3.5 million years ago
What were the first prokaryotic cells like?
The first prokaryotic cells were anaerobic and heterotrophic
Why did the first prokaryotic cells evlove into archebacteria?
Because eventually they used up all the food and evloved into archebacteria
define archebacteria
prokaryotes that live in harsh environments
what do archebacteria use for food?
chemosynthesis
define chemosynthesis
to use chemicals in the environment for food
What does prokaryote photosynthesising envolve?
prokaryotes used energy from the sun to make food
What led to an increase in oxygen in Earth atmosphere?
Prokaryotes photosynthesising gave off oxygen
How did plant and animal cells form?
Endosymbiosis
define endosymbiosis
When one organism lives inside another organisms
