The Four Spheres
This sphere includes all living things on Earth.
What is the biosphere?
This term describes any living part of an ecosystem.
What is biotic?
This is the organism at the very start of almost every food chain, since it makes its own energy from the sun.
What is a producer?
This is the position of producers on an energy pyramid — top, middle, or bottom?
What is the bottom?
These gases in the atmosphere trap heat from the sun, keeping Earth warm enough to support life.
What are greenhouse gases?
Rock, soil, and mountains — including the Yukon's own bedrock — belong to this sphere.
What is the geosphere?
Permafrost, sunlight, and temperature are all examples of this kind of factor.
What is abiotic?
A grizzly bear eating a salmon is an example of this feeding relationship.
What is predator-prey?
As energy moves up an energy pyramid, this generally happens to the amount of energy available at each level.
What is it decreases?
These are the winds that blow near the equator and move air (and surface water) from east to west.
What are the trade winds?
This term describes all the water on Earth, whether liquid, ice, or vapour — including glaciers in the St. Elias Mountains.
What is the hydrosphere?
What is an example of an abiotic factor that might affect biodiversity in an ecosystem?
Sunlight, temperature, precipitation, air quality etc.
This term describes an organism, like a bear, that eats both plants and animals.
What is an omnivore?
This is the rough percentage of energy that transfers from one trophic level to the next.
What is 10%?
This is the name for the massive system of deep-water currents created when cold, salty (and therefore denser) water sinks and circulates around the globe.
What is the global (ocean) conveyor belt?
When a wildfire burns boreal forest, releasing carbon into the air and ash onto the soil, it's showing an interaction between these two spheres (name both).
What are the biosphere and atmosphere (accept geosphere too)?
Permafrost melting causes trees to lean. What type of factor is affected? What type of factor is affecting? What type of interaction is this?
Biotic affected by abiotic, direct interaction
Unlike a food chain, this diagram shows multiple overlapping feeding relationships in an ecosystem — for example, how chinook salmon connect bears, eagles, and even forest soil.
What is a food web?
This is why energy pyramids usually have very few levels — rarely more than four or five.
What is there isn't enough energy left after several transfers to support another level?
These are the wind belts found between 30° and 60° latitude in both hemispheres — the ones that most affect weather across North America.
What are the westerlies?
This is the term for when one sphere directly affects another without a "middleman" — e.g., rain (hydrosphere) falling straight onto soil (geosphere).
What is a direct interaction?
A dead salmon decomposing on a riverbank still counts as this type of factor, even though it's no longer alive — because of what it was and what it's made of, not whether it's currently living.
What is Biotic?
When spawning salmon die after returning to Yukon rivers, their bodies release nutrients into the forest — this is a real example of matter doing this, connecting the hydrosphere and biosphere.
What is cycling (nutrient cycling)?
A top predator like a wolf or grizzly occupies this position on the pyramid, and this is why there are always fewer of them than there are producers.
What is the top (fewer individuals because less energy is available)?
This is the key difference scientists point to between the natural greenhouse effect (which has existed for millions of years) and current climate change.
What is the human-caused increase in greenhouse gases, intensifying the effect beyond its natural level? (accept: enhanced/intensified greenhouse effect)