Earth's History and Evolution

These flashcards cover essential concepts of Earth's history, the evolution of life, and key scientific theories and experiments related to the emergence of life.

Geologic Time Scale

A system used to describe the timing and relationship of events in Earth's history.

Cambrian Explosion

A period in Earth's history around 541 million years ago marked by a rapid diversification of life forms.

Miller-Urey Experiment

An experiment that simulated early Earth conditions, demonstrating that organic compounds could be formed from inorganic precursors.

Primordial Soup

The theoretical mixture of organic compounds in early Earth’s oceans, necessary for life to originate.

Cyanobacteria

Photosynthetic bacteria that played a major role in producing oxygen during the Great Oxygenation Event.

Endosymbiosis

A theory that explains the origin of eukaryotic cells from prokaryotic organisms through a symbiotic relationship.

Anaerobic Respiration

A type of respiration that occurs without oxygen, used by early life forms like bacteria.

RNA World Hypothesis

A proposal that early forms of life were based on RNA, which can replicate and perform catalytic functions.

Photosynthesis

The process by which green plants and some other organisms use sunlight to synthesize foods with the help of carbon dioxide and water, releasing oxygen as a byproduct.

Oxygen Revolution

The increase of oxygen in Earth's atmosphere due to photosynthetic organisms, leading to significant changes in the environment and life forms.

Eukaryotes

Organisms whose cells have a nucleus enclosed within membranes, including organisms like plants and animals.

Metabolic Pathways

A series of chemical reactions occurring within a cell that lead to the conversion of a substrate into a product.

Homo Sapiens Sapiens

The subspecies of modern humans, which emerged around 200,000 years ago.

Prokaryotes

Single-celled organisms that lack a nucleus, including archaea and bacteria.

Sexual Reproduction

A process that involves the combination of genetic material from two parents to produce offspring.

Trilobites

Extinct marine arthropods that were abundant during the Paleozoic Era, especially in the Cambrian period.

Fossil

The preserved remains or traces of ancient living organisms.