Essential Idea
The structure of an ecosystem is based on its biotic and abiotic components.
Assessment Statements
2.1.1 Distinguish between biotic and abiotic components of an ecosystem.
2.1.2 Define the term trophic level.
2.1.3 Identify and explain trophic levels in food chains and webs selected from local environments.
2.1.4 Explain the principles of pyramids of numbers, biomass and productivity, and construct them from given data.
2.1.5 Discuss how pyramid structure affects the functioning of an ecosystem.
2.1.6 Define the terms species, population, habitat, niche, community and ecosystem in reference to local examples.
2.1.7 Describe and explain population interactions (population or community relationships) using named species.
Key Vocabulary
Biotic
Abiotic
Trophic level(s)
Producer
Consumer
Herbivore
Carnivore
Decomposer
Food chain
Food web
Pyramid of...
Numbers
Biomass
Productivity
Bioaccumulation
Biomagnification
Half life
Species/Organism
Population
Community
Ecosystem
Habitat
Niche
Competition
Predation
Parasitism
Mutualism
Herbivory
"Topic 2.1: Part 1" by NicheScience (11:56)
This video tutorial outlines the concepts related to the key vocabulary above.
"Topic 2.1: Part 2" by NicheScience (17:47)
This video tutorial outlines the concepts related to the key vocabulary above.
"Topic 2.1: Part 3" by NicheScience (8:34)
This video tutorial outlines the concepts related to the key vocabulary above.
This video examines ecosystem structure, biomes and some ecosystem stability.
This video examines the differences between a fundamental and realized niche
and how organisms cannot occupy the same niche due to competitive exclusion.
"Dead Stuff and Our Food Chain" by TED-Ed (3:50)
This video examines the relationship between detritus (dead organic matter)
and the rest of the food chain/web, bringing human consumption into
perspective as it demonstrates our connection to this base layer of our ecosystems.
"Trophic Cascades and Rewilding" by TED-Ed (5:27)
This video outlines the processes by which certain species can completely
influence an entire ecosystem. It uses the case study of reintroducing wolves
to Yellowstone National Park and their affect on the rivers, trees and other small animals.
"Elements of Biology: Ecosystems" by Discovery Channel (stop at 17:35)
**This video includes most of the terms from the Key Vocabulary list above,
plus several others that we'll examine throughout the course.
This video examines the fundamental concepts related to ecology.
Resource - Annotated description.