General Biology 2 Reviewer - Fourth Quarter

Flashcards covering key vocabulary terms related to evolution, geologic time scale, and systematics.

Geologic Time Scale

Organizes Earth's history into major intervals based on significant events in Earth's physical, chemical, and biological development.

Precambrian Eon

Includes the Hadean, Archean, and Proterozoic eons; makes up nearly 88% of Earth's history.

Paleozoic Era

Began with the Cambrian Explosion, featuring rapid diversification of life in the oceans and ending with the Permian Extinction.

Mesozoic Era

Known as the “Age of Reptiles,” featuring the evolution of dinosaurs, early birds, and flowering plants. Ended with the Cretaceous Mass Extinction.

Cenozoic Era

Known as the “Age of Mammals,” featuring rapid mammalian and bird diversification and the evolution of primates and humans.

Mass Extinction

Widespread and rapid decrease in biodiversity, where large numbers of species go extinct in a short geological time frame.

Permian Extinction

Caused massive marine and terrestrial losses; possibly due to volcanic activity or climate shifts.

Cretaceous Extinction

Often linked to an asteroid impact; led to the extinction of dinosaurs and marine reptiles.

Mutation

A random change in DNA that may create a new trait and serves as the raw material for evolution.

Natural Selection

The process where organisms with advantageous traits are more likely to survive and reproduce.

Genetic Drift

Random changes in allele frequencies, especially in small populations, which can lead to the loss of genetic variation.

Gene Flow

Movement of genes between populations, which can introduce new traits or maintain genetic similarity between groups.

Geographic Isolation

Physical separation of populations that prevents interbreeding and leads to speciation.

Homologous Structures

Structures with similar anatomy but different functions, indicating a shared ancestor.

Vestigial Structures

Body parts that have lost their original function through evolution.

Embryological Similarities

Similarities in early development stages suggest common ancestry.

Molecular Evidence (DNA)

DNA similarities reveal how closely related species are.

Systematics

The scientific study of how organisms are classified based on their evolutionary relationships.

Phylogenetic trees and cladograms

Branching diagrams used to show evolutionary relationships between species based on traits and common ancestry.

Cladistics

A method of classification based on shared derived traits.