Chapter 1
Earth Science
Course: Elementary Education Multiple Subjects 7001
Subject: Elementary Education Science Subtest 7005
Chapter: Life Science
All living organisms exist within complex networks of interactions, depending on both biotic (living) and abiotic (nonliving) factors to survive, grow, and reproduce. Interdependence refers to these relationships and how disruptions in one part of a system can affect the whole. Ecological study emphasizes the dynamic balance among organisms and their environment, often categorized into levels of organization: individual, population, community, ecosystem, biome, and biosphere.
1. Ecosystems and Ecological Structure
An ecosystem includes all organisms in a given area and the physical environment with which they interact. Ecosystems are open systems—they receive energy (usually from the sun) and exchange materials with surrounding systems.
Abiotic components include:
- Climate: temperature, precipitation, light
- Geography: topography, elevation
- Soil composition: nutrients, minerals
- Water availability and salinity
Biotic components include: