Mr. Bebe discusses the cycling of matter in ecosystems, focusing on the water, carbon, and nitrogen cycles. He explains how microorganisms play a role in maintaining and disrupting ecosystems, highlighting processes like decomposition and nitrogen fixation. The video also covers human and natural disruptions to ecosystems, such as poor farming practices and natural disasters.

What is the primary process by which water returns to the ocean in the water cycle?

• Precipitation

• Transpiration

• Evaporation

• Condensation

Which form of carbon is most commonly found in the atmosphere?

• Glucose

• Carbon monoxide

• Methane

• Carbon dioxide

What are carbon sinks?

• Regions with high carbon emissions

• Zones with no carbon presence

• Areas where carbon is stored

• Places where carbon is released

What percentage of the atmosphere is composed of non-usable nitrogen?

• 10%

• 21%

• 78%

• 50%

What process converts non-usable nitrogen into a usable form?

• Respiration

• Nitrogen fixation

• Decomposition

• Photosynthesis

How do microorganisms contribute to the decomposition process?

• By fixing nitrogen

• By consuming sunlight

• By recycling organic matter

• By producing oxygen

What is the role of mycorrhizae in plant health?

• They provide sunlight to plants

• They fix nitrogen for plants

• They help plants absorb more nutrients

• They decompose plant matter

What is a consequence of algal blooms in aquatic ecosystems?

• Reduced water temperature

• Increased oxygen levels

• Enhanced plant growth

• Decreased sunlight for plants

Which human activity is a major contributor to ecosystem disruption?

• Using renewable energy

• Recycling waste

• Burning fossil fuels

• Planting trees

Which natural event can disrupt an ecosystem?

• Cloud formation

• Rainfall

• Volcano eruption

• Photosynthesis