Approximately how many years ago did Earth's history begin with its formation?
4.6 billion years ago.
Swan-necked flask.
What does RNA stand for?
Ribonucleic Acid
These two scientists made a groundbreaking discovery that showed amino acids (and other biomolecules) could be synthesized from inorganic material.
What is the name for the earliest model of a cell?
Protocell
Where is it believed that life first began on Earth?
In the oceans, near hydrothermal vents.
Describe the experimental setup and results for the 3 jars in Redi's experiment.
Jar 1 - Meat covered with cork/paper = no maggots inside or outside
Jar 2- Meat covered with gauze - maggots grew on top of gauze, none on the meat inside.
Jar 3- Meat uncovered - maggots grew on meat inside.
What is the name of the RNA molecule that can catalyze chemical reactions, similar to a protein enzyme.
Ribozyme
Who was the first to coin the term "spontaneous generation"?
These two scientists who lived in separate countries independently proposed similar ideas about the conditions that may have led to the origin of life on Earth.
Russian scientsit Aleksandr Oparin
English scientist John Burdon Sanderson (J. B. S) Haldane
What two things are required for the essential elements and compounds on early Earth to react?
Pasteur set out to design a flask based on criticism from Spallanzani's experiment. What did critics claim about Spallanzani's design?
Critics said that boiling the broth too long had destroyed the invisible "life force" in the broth. They said that cool fresh air was needed to supply the necessary magic life force.
Why did DNA later replace RNA as the molecule to store information?
It is more stable due to:
The deoxyribose in the DNA sugar-phosphate backbone makes DNA chemically more stable.
The hydrogen bonds holding together the double-helical structure of DNA add additional stability.
Use of thymine rather than uracil further enhances DNA stability.
The results of these two scientists contracticted each other.
Spallanzani and Needham
What are the three different types of membranes?
Vesicle
Micelle
Bilayer
Prebiotic Earth experienced high levels of UV radiation, why?
It lacked a significant amount of oxygen in its atmosphere, which is necessary for the formation of ozone, the protective layer that shields the planet from harmful UV rays.
The oceanic compartment
The atmospheric compartment
Condenser
Electrode
What is the name of the idea that in the early stages of life on Earth, RNA molecules were the primary carriers of genetic information and performed catalytic functions,
The RNA World Hypothesis
What is the full name of the scientist who developed modern germ theory.
Louis Pasteur
What are the 4 steps of the Oparin-Haldane hypothesis?
1) Synthesis of simple organic molecules from inorganic compounds.
2) Polymerization
3) Self-replicate
4) Creation of a protocell through packaging with a membrane.
Name the 5 gases present on prebiotic Earth WITH their chemical formulas.
Methane - CH4
Carbon Dioxide CO2
Nitrogen N2
Hydrogren H2
Ammonia NH3
John Needham's experiments on spontaneous generation had several flaws. List 3.
Why is RNA and not DNA thought to have given rise to life?
These two gentlemen together disproved the theory of spontaneous generation for both macroscopic and microscopic organisms.
Louis Pasteur
What is the Murchison meteorite and why is it significant in the quest for the origin of life?
In 1969, the Murchison meteorite smashed into Australia. One of the oldest known remnants of the pre-Earth solar system, this meteorite played a pivotal role in confirming the presence of carbon molecules elsewhere in the universe.