Origins of the First Cells

Flashcards covering the origins of the first cells, including abiotic synthesis, the Miller experiment, the role of RNA and ribozymes, and the formation of liposomes.

Abiotic Synthesis

The non-living synthesis of simple organic compounds like amino acids and nitrogenous bases.

Abiotic Polymerization

The non-living process where simple organic monomers combine to form macromolecules such as nucleic acids or proteins.

Emergence of Self-Replicating Macromolecule

A critical phase in the origin of cells, involving the appearance of a macromolecule capable of both storing genetic information and self-replication.

Encapsulation (First Primitive Cell)

The final phase in cell origins, where a 'living' molecule is enclosed within a simple membrane, forming the first primitive cell.

Stanley Miller Experiment

An experiment that used an apparatus to simulate early Earth conditions (boiling water, electrical discharge, specific gases) and produced simple organic compounds like amino acids, suggesting life's building blocks could form abiotically.

Products of Modified Miller Experiments

Include numerous amino acids, formaldehyde, formic acid, hydrogen cyanide, simple sugars, and adenine (a nitrogenous base).

DNA Replication Paradox

The problem that DNA replication requires protein catalysts (enzymes), but these enzymes cannot be produced without the genetic information found in DNA, leading some scientists to look to RNA as the original informational molecule.

Protein Catalyst

A protein, also known as an enzyme, that speeds up chemical reactions.

Ribonucleotides

The building blocks of RNA polymers, which are capable of forming abiotically.

Ribozymes

Catalytic RNA molecules, discovered by Sidney Altman and Thomas Cech in the 1980s, that can fold into enzyme-like shapes and catalyze chemical reactions.

Liposomes

Hollow membrane-bound vesicles of varying sizes that form spontaneously when lipids are mixed with water, capable of 'reproducing' by splitting and performing simple metabolic reactions.