Bio Early Life SEP 2019

What evidence do we have of the age of the Earth?

• Fossils

• Moon rocks that are 3 billion years old

• Earth rocks that are 4.5 billion years old

• Meteorites that are 13 billion years old

How do we know how old rocks are?

• We find them in volcanoes

• We find them at the bottom of the ocean

• We know how long it takes radioactive isotopes to decay

• We find them at the top of mountains

Why is it important for Life that the Earth is very old?

• Evolution takes a long time

• It's not important for Life

• That way we can have really old fossils

• Genetics cannot happen unless you have a long time

Why is it important that we have a large moon?

• Because it causes ocean tides

• Because we can see at night when the moon is full

• Because it gives us a place to get resources

• To stabilize the Earth's axis

Which is False about the Early Earth?

• There was a lot of Carbon Dioxide in the atmosphere

• We had Hydrogen in Water, Methane, and Ammonia

• There was no Nitrogen in the atmosphere

• There was very little pure Oxygen in the atmosphere

Which was NOT present in Early Earth?

• Volcanoes and Geothermal Activity

• A thick Ozone layer (O3)

• Lightning in the atmosphere

• Ultra-Violet Rays from the Sun

How did water contribute to chemical reactions that made the first cells on Early Earth?

• Water is the Universal Solvent

• Water is pH neutral

• Water disperses sunlight

• Water moderates temperature

• All of the above

Which is NOT a theory of how life started on Earth?

• Life started in shallow pools of water

• Life started in hydrothermal vents deep under the ocean

• Life started on land with a bolt of lightning

• Life came to Earth frozen in water on a comet

Which Molecule of Life is thought to be critical to the origin of life on Earth?

• RNA because it can replicate itself and code for proteins

• Sugar because it is built from photosynthesis

• Water because it is a non-polar molecule

• Methane because it is made of Carbon and 4 Hydrogens

Which is False about sugar molecules?

• Sugar can be made in to fatty acids by rearranging the Carbon, Hydrogen, and Oxygen molecules

• Sugar is a key part of DNA and RNA

• Add some Nitrogen (and perhaps Phosphorus and Sulfur) and we can change sugar in to a protein

• It does not take energy to build a sugar molecule