SNC1W1 Ecology

Ecosystems

100

What is the term for the place where an organism lives?

Habitats

200

Name the four spheres

Atmosphere, lithosphere, hydrosphere, biosphere

300

What is the difference between a population and a community?

A population is all individuals of one species in an area.
A community is all the populations living in an area.

400

Explain the difference between biotic and abiotic factors and give one example of each.

Biotic factors are living things or their remains/products. Example: plants, bacteria.
Abiotic factors are non-living components. Example: water, temperature, sunlight.

500

A forest contains trees, fungi, insects, soil, streams, sunlight, and rocks. Explain why this entire area is considered an ecosystem.

It is an ecosystem because living organisms interact with each other and with non-living components such as water, sunlight, rocks, and soil.

Energy Flow

100

What process converts light energy into chemical energy?

Photosynthesis

200

Name the organisms that make their own food.

Producers

300

In an energy pyramid, about what percentage of energy is transferred to the next trophic level?

10%

400

State the word equation for cellular respiration.

Sugar + oxygen → carbon dioxide + water + energy

500

A food chain contains grass → rabbit → fox → wolf.
Identify the trophic level of each organism.

• Grass = 1st trophic level (producer)

• Rabbit = 2nd trophic level (herbivore)

• Fox = 3rd trophic level (carnivore)

• Wolf = 4th trophic level (top carnivore)

Human Impact

100

What is pollution?

The release of harmful contaminants into the environment.

200

What type of forest harvesting removes most or all trees from an area?

Clear-cutting

300

What is an invasive species?

A non-native species that spreads rapidly and harms ecosystems.

400

Explain one environmental problem caused by pesticides.

• Harm non-target species

• Cause bioaccumulation or bioamplification

• Pollute water

• Lead to pesticide resistance

500

Compare natural ecosystems and agroecosystems using TWO differences.

• Natural ecosystems have high biodiversity; agroecosystems usually have low biodiversity.

• Natural ecosystems sustain themselves; agroecosystems require human management.

• Agroecosystems often use monocultures and pesticides.

Biodiversity and Succession

100

What is biodiversity?

The variety of life in an area.

200

What is the name for the gradual replacement of communities after a disturbance?

Ecological succession

300

What is the difference between primary and secondary succession?

Primary succession begins where no soil or life exists.
Secondary succession occurs where soil remains after a disturbance.

400

Why does habitat fragmentation threaten species survival?

It divides ecosystems into smaller areas, reducing resources, increasing pollution exposure, and isolating populations.

500

A wildfire destroys most plants in a forest, but the soil remains. Describe the stages of succession that may follow.

Secondary succession occurs:

1. Grasses and small plants grow first
2. Shrubs and young trees appear
3. Larger trees grow
4. A stable mature forest community develops again

Biomes and Aquatic Ecosystems

100

What biome is the northernmost biome with permafrost and a short growing season?

Tundra

200

Which biome is dominated by coniferous trees and is the largest biome in Canada?

Boreal forest

300

What is the difference between oligotrophic and eutrophic lakes?

• Oligotrophic lakes have low nutrients, clear water, and are usually deep.

• Eutrophic lakes have high nutrients, murky water, and high productivity.

400

Explain why grasslands have very fertile soil.

Grasslands have rich black soil because grasses die and decompose each year, adding organic matter and nutrients to the soil.

500

Compare freshwater and marine ecosystems using TWO differences.

• Freshwater ecosystems have less than 1% salt, while marine ecosystems have about 3% salt.

• Marine ecosystems cover much more of Earth’s surface.

• Rivers and lakes are freshwater; oceans are marine ecosystems.

• Marine ecosystems are responsible for most evaporation in the water cycle.