A2.1.3 Challenge of explaining the spontaneous origin of cells

What are the four key developments required for the origin of the first cells?

Catalysis

Self-replication

Self-assembly

Compartmentalization.

Why is RNA considered a plausible candidate for the first genetic material?

RNA can store genetic information, catalyze its own replication, and act as a catalyst (ribozyme) for biochemical reactions.

What is catalysis?

The process of increasing the rate of a chemical reaction by using a substance called a catalyst, which is not consumed during the reaction.

What was the significance of the Miller-Urey experiment?

It demonstrated that organic molecules, such as amino acids, could form spontaneously under simulated early Earth conditions.

What are ribozymes?

RNA molecules that can act as catalysts to drive biochemical reactions.

What is self-assembly in the context of the origin of life?

The spontaneous linking of simpler molecules to form complex polymers, such as proteins and nucleic acids.

Why do phospholipids spontaneously form bilayers in water?

Phospholipids are amphipathic molecules with hydrophilic heads and hydrophobic tails that naturally assemble into bilayers when mixed with water.

What is the role of compartmentalization in the origin of cells?

Compartmentalization allows for the separation of chemical reactions and processes, creating distinct environments for cellular functions.

What is the importance of testable hypotheses in science?

Testable hypotheses allow scientists to investigate and validate theories through experimentation and observation.

What are the building blocks of proteins?

Amino acids.

What is the structural foundation of cell membranes?

Phospholipid bilayers.

What is the chicken-and-egg problem in DNA replication?

DNA replication relies on enzymes, which are encoded by DNA itself, creating a paradox of which came first.

What three unique properties make RNA a strong candidate for the first genetic material?

RNA can store genetic information

RNA can catalyze its own replication

RNA can act as a catalyst (ribozyme) for biochemical reactions.

What are three ways scientists use to investigate the origins of life?

Laboratory simulations

Comparative genomics

Mathematical and computer models.