Introduction to Ecosystems and Biomes

What is an ecosystem?

• A dynamic complex of plant, animal, and microorganism communities and their non-living environment interacting as a functional unit.

• A large geographical region characterized by its climate, soil type, and distinct plant and animal communities.

• A group of organisms of the same species living in a specific area.

• Different populations of various species living together.

What are producers?

• Organisms that synthesize organic molecules from inorganic substances.

• Organisms that cannot produce their own food.

• Organisms that obtain energy and nutrients by feeding on other organisms.

• Microorganisms that break down dead plants and animals.

What is the carbon cycle?

• Describes the movement of carbon among the atmosphere, biosphere, hydrosphere, and geosphere.

• Describes how nitrogen moves through the atmosphere, living organisms, soil, and water.

• Describes the natural, continuous movement of water on, above, and below the surface of the Earth.

• Describes how sulfur moves through the atmosphere, living things, soil, water, and rocks.

What is a biome?

• A large geographical region characterized by its climate, soil type, and distinct plant and animal communities.

• A dynamic complex of plant, animal, and microorganism communities.

• A group of organisms of the same species living in a specific area.

• Different populations of various species living together.

What are the main steps in the nitrogen cycle?

• Nitrogen fixation, nitrification, assimilation, ammonification, denitrification.

• Photosynthesis, respiration, decomposition, combustion, carbon sequestration.

• Weathering of rocks, absorption by plants, consumption by animals, decomposition, sedimentation.

• Evaporation, transpiration, condensation, precipitation, runoff.

What is the importance of the hydrologic cycle?

• It regulates Earth’s climate and sustains ecosystems by distributing fresh water.

• It describes how sulfur moves through the atmosphere.

• It describes the movement of carbon among different spheres.

• It maintains ecosystem health by recycling nitrogen.

What is the main impact of human activity on the nitrogen cycle?

• Fertilizer overuse leads to water pollution.

• Urbanization leads to habitat loss.

• Logging leads to deforestation.

• Climate change impacts biodiversity.

What characterizes a tropical rainforest?

• Hot and humid year-round with very high rainfall.

• Warm temperatures year-round with distinct wet and dry seasons.

• Extremely dry climate with large day-night temperature shifts.

• Hot, dry summers and cool, moist winters.

What is the human impact on savannas?

• Overgrazing by livestock and conversion to farmland.

• Deforestation for logging and agriculture.

• Urbanization and habitat fragmentation.

• Increased fire frequency due to human activity.

What is the climate of a desert biome?

• Extremely dry; can be hot or cold.

• Hot and humid year-round.

• Long, cold winters and short, mild summers.

• Very cold with low precipitation.