Ecology & Evolution Study Guide

Photoautotrophs

Organisms that use sunlight to produce food through photosynthesis.

Chemoautotrophs

Organisms that obtain energy by oxidizing inorganic substances.

Heterotroph

Organism that consumes other organisms for energy.

Endotherm

Organism that regulates its body temperature internally.

Ectotherm

Organism that relies on external environment for body heat.

Metabolic Rate vs. Body Size

Smaller organisms have higher metabolic rate per unit body mass.

Carrying Capacity

Max population an environment can support.

Density-Dependent Factors

Factors affected by population size.

Density-Independent Factors

Factors unrelated to population size.

Keystone Species

A species with a disproportionately large effect on its environment.

Homologous Structures

Structures that are similar in different species due to shared ancestry.

Analogous Structures

Structures that serve similar functions but have different evolutionary origins.

Allele

Variant of a gene.

Cladogram

Diagram showing evolutionary relationships.

Punctuated Equilibrium

Model of evolution characterized by rapid changes followed by stability.