Origin of Life

What is the process by which smaller, simple molecules became progressively larger and more complex?

• Biological evolution

• Chemical evolution

• Chemical polymerization

• Biomonomerization

How did simple molecules become polymers in Earth's early atmosphere?

• By condensing under extreme heat and pressure deep within the Earth's crust.

• Through the catalytic action of metal ions present in primordial oceans.

• Due to exposure to ultraviolet radiation and electrical discharges such as lightning.

• By being transported to Earth on meteorites and comets that bombarded the planet.

What is one hypothesis for how RNA FIRST formed?

• Through the gradual accumulation of dust particles in the Earth's early atmosphere.

• By the replication of simpler precursor molecules inside lipid bilayers.

• As a result of direct delivery to Earth via interstellar comets.

• Through the synthesis of organic molecules on the surfaces of clay minerals.

Which of the following molecules was hypothesized to be the earliest form of "life" and was subject to natural selection?

• DNA

• Proteins

• RNA

• Lipids

How did progenotes (early cells) arise from polymer complexes (RNA, DNA, proteins)?

• Chemical reactions between polymers created oxygen, water, and other molecules necessary to sustain life.

• By binding with metal ions in the ocean, which acted as catalysts for their transformation into living cells.

• They were engulfed by self-assembling lipid bilayers, facilitating a basic metabolism and replication.

• Through gradual accumulation of genetic material, leading to the formation of simple cellular structures capable of reproduction.

Why was the Miller-Urey experiment important?

• It showed that life could be created in a lab from basic molecules.

• It demonstrated Earth’s early atmosphere could have given rise to organic molecules.

• It demonstrated how the first cells arose on Earth.

• It showed that RNA was the first self-replicating molecule.

Early Earth was too harsh for life to form, but what provided energy for larger macromolecules to form simple molecules?

• Lightning

• Volcanic ash

• Clay minerals

• Dust particles

Why was RNA considered to have "evolved" first?

• A. It can carry genetic information and perform important cellular functions

• B. It is a more stable molecule than DNA

• C. It can self-replicate

• D. Both a and c

• E. All of the above

Which evolved first?

• Cellular Respiration

• Photosynthesis

• Aerobic Respiration

• Eukaryotes

Why did photosynthetic organisms pave the way for more diverse life forms 500 million years ago?

• They increased the amount of oxygen in the air

• They increased the number of organic molecules

• They increased the amount of energy production

• They provided new habitats for species to live in