W8 L1 - Habitability Flashcards
What does life need?
TESS - 1) Environment of reduction oxidation reactions, 2) solvent/medium eg water, 3) self-replicating material (DNA/RNA), 4) time
What is the habitable zone?
The distance from the star where water can exist as liquid on the surface; on an Earth-like planet
How long ago did the Earth form?
4.5bn years ago
How soon after the Earth formed did life appear?
Within 400 million years; at 4.1bn years we have evidence
What are the two types of information storage molecule that all life on Earth is based on?
RNA and DNA
What are the four bases in RNA?
A U G C
What are the four bases in DNA?
A T C G
What are the sugar backbones used in RNA and DNA respectively?
Ribose, and deoxyribose
Name three things found in comets that contribute to life
Water, sugars (ribose), and amino acids
Is the first evidence of life on Earth found before or after the late heavy bombardment ended?
Before!
What early life form is found in Western Australia that produced oxygen in the atmosphere?
Stromatolites
What is the concept called where life can regulate and later a planet in response to environmental changes
The Gaia Hypothesis
What is the name for lifeforms living in extreme environments?
Extremophiles
Name one moon of Jupiter where liquid water and life may exist?
Europa
Name two moons of Saturn where life may exist
Enceladus and Titan
