A2.1 Origin of cells HL ONLY Flashcards
What were the conditions of prebiotic earth?
-Low oxygen levels
-High carbon dioxide levels
-High in methane
-High temperature levels
-No atmosphere
Why did the environment change?
The environment changed because once living things arose they started to produce things like oxygen forming an ozone layer
What is the result of earths pre-biotic environemntal changes?
The result is that we don’t see any more spontaneous generation
What can living things do?
-Living things can and are self sustaining
-Living things can pass this highly ordered state onto offsprings
What does self sustaining mean?
Self-sustaining means using energy from the outside in order to maintain a highly ordered state
How do we know cells are living and are the smallest unit of life?
Cells are the smallest components that:
-Use energy to maintain order if not they die
-New cells can produce more cells
-Cells can live outside of the body
What was the goal of the Miller-Urey experiment?
The goal of the Miller-urey experiment was to show how life on earth arose out of non-living matter
How did the first cell separate itself from the environment?
The first cell seperated itself from the enivronment because compartment regions that were semi-permeable spontaneously arose
What are vesicles?
Vesicles are structures surrounded by membranes
How are vesicles separated from the environment?
Vesicles are separated from the environment by phospholipid bilayer
What was the first genetic material?
Ribonucleic acid
What is evidence for RNA being the first genetic material?
-It is self replicating
-It mutates quicker than DNA since it does not have complementary base pairing and mutation leads to diversity
What does LUCA stand for?
LUCA stands for Last Universal Common Ancestor
What is evidence for LUCA?
-All organisms use DNA and all DNA work the same way
-Similarities in ribosome structure
-Similarities in how DNA and RNA are synthesised
How long ago did life form?
4.1-4.5B years
