RNA World
What molecule is central to the "RNA World" hypothesis for the origin of life?
RNA
What famous experiment demonstrated that electric sparks could create amino acids from simple gases?
The miller-Urey experiment
Where does the deep-sea vent theory suggest life began?
At submarine hydrothermal vents
What does the panspermia theory propose about the origin of life?
Life came to Earth from elsewhere in space
What substance does the clay theory suggest helped organize the first molecules of life?
Clay crystals
According to the RNA World theory, what can RNA do that makes it unique among biological molecules?
Store genetic information and act as an enzyme
Which gases were used in the Miller-Urey experiment to simulate early Earth's atmosphere?
Water, methane, ammonia and hydrogen
What elements, crucial for life, are spewed from these vents?
Carbon and hydrogen
What celestial bodies are suggested as possible carriers of life to Earth?
Meteorites or comets
Who proposed the idea that clay could have played a role in the origin of life?
Alexander Graham Cairns-Smith
What two molecules are thought to have replaced RNA as the main carriers of genetic information and catalytic activity?
DNA and proteins
What natural phenomenon is proposed to have provided the "spark" for life in this theory?
Lightning
What do the rocky nooks at hydrothermal vents provide for early life?
Concentration of molecules and mineral catalysts
What planet's meteorites have been controversially suggested to bring microbes to Earth?
Mars
According to the ice theory, what covered Earth's oceans 3 billion years ago?
Ice
What is a major challenge or question for the RNA World hypothesis?
How RNA could have formed spontaneously on early Earth
What key building blocks of life were produced in the Miller-Urey experiment?
Amino acids and sugars
What kind of energy do hydrothermal vents provide that could have supported early life?
Chemical and thermal energy
What is a major criticism of the panspermia theory?
It does not explain how life began, just how it arrived on Earth
What benefit did the ice provide to early organic molecules?
Protection from UV light and cosmic impacts
Name one alternative nucleic acid to RNA that has been suggested as a precursor to life.
TNA or PNA
Why is the original Miller-Urey experiment sometimes criticized today?
The early Earth's atmosphere may have been hydrogen-poor, unlike the experiment's setup
What modern scientific achievement supports the plausibility of the deep-sea vent theory?
Creation of protocells under similar hot, alkaline conditions
What term describes the process of life being distributed throughout the universe via space debris?
Panspermia
How might clay crystals have helped early organic molecules?
By arranging them into organized patterns, similar to how genes work