Ecological Relationships and Energy Flow

This video reviews key concepts from Unit 1, covering ecosystems, biomes, and cycles. It explains relationships like symbiosis and competition, and details terrestrial and aquatic biomes. The video also discusses the carbon, nitrogen, phosphorus, and water cycles, highlighting human impacts. It covers primary productivity, trophic levels, and energy flow, and concludes with food chains, webs, and feedback loops.

Which of the following relationships is characterized by one organism benefiting while the other is unaffected?

• Mutualism

• Commensalism

• Parasitism

• Predation

Why are deserts considered the most fragile biome?

• They are rich in biodiversity.

• They lack sufficient warmth and water.

• They have high primary productivity.

• They have high nutrient recycling.

What role do phytoplankton play in aquatic ecosystems?

• They are primary consumers.

• They store CO2 and produce O2.

• They decompose organic matter.

• They are top predators.

How do humans impact the phosphorus cycle?

• By reducing phosphate in fertilizers.

• By mining rocks for phosphate.

• By increasing gaseous phosphorus.

• By increasing atmospheric phosphorus.

Which biome is known for having the highest net primary productivity?

• Coral reefs

• Tundra

• Deserts

• Grasslands

What is the primary source of energy for all trophic levels?

• The Moon

• The Sun

• The Earth

• The Ocean

In a food web, what happens if a primary consumer is removed?

• Tertiary consumers increase.

• Secondary consumers decrease.

• Producers decrease.

• Secondary consumers increase.

What is a characteristic of a positive feedback loop?

• It stabilizes the system.

• It amplifies changes in the system.

• It requires no energy input.

• It decreases system intensity.

Which process is an example of a negative feedback loop?

• Body temperature regulation

• Global warming

• Deforestation

• Ocean acidification

What percentage of energy is typically transferred from one trophic level to the next?

• 90%

• 50%

• 10%

• 1%