ecology study guide

What is the biosphere?

The part of Earth where life exists, including land, water, and atmosphere.

What is equilibrium in an ecosystem?

A stable system where biotic and abiotic factors maintain balance over time.

Define biodiversity.

The variety of life in an ecosystem, contributing to stability and resilience.

What are the trophic levels in an ecosystem?

Producers (Autotrophs) → Primary Consumers → Secondary Consumers → Tertiary Consumers.

What does an energy pyramid show?

It shows energy loss at each level of the food chain, where only ~10% of energy is passed on.

What is primary productivity?

The rate at which producers convert solar energy into chemical energy.

What do the First and Second Laws of Thermodynamics state?

Energy cannot be created or destroyed, only transformed, and every energy transfer loses some energy as heat.

What is the hydrologic cycle?

The cycle of water movement through precipitation, transpiration, percolation, and runoff.

What causes acid deposition?

Sulfur dioxide (SO₂) and nitrogen oxides (NOₓ) react with water to form acid rain.

What are some effects of acid deposition?

Lowers pH of water bodies, harming aquatic life, and damages plants, soil, and buildings.

What is the importance of carbon in ecosystems?

Carbon is the backbone of organic molecules such as carbohydrates, proteins, fats, and DNA.

What are the processes in the carbon cycle?

Photosynthesis, cellular respiration, and combustion.

What is denitrification?

The process where anaerobic bacteria convert nitrates back to nitrogen gas (N₂).

What is eutrophication?

A process caused by excess nutrients in water leading to algal blooms that deplete oxygen.

What is the role of phosphorus in living organisms?

Phosphorus is needed for DNA, ATP, and bones.

Why is the greenhouse effect significant?

Greenhouse gases trap heat in the atmosphere, affecting global temperatures.

What is nitrogen fixation?

The process where lightning or bacteria convert nitrogen gas (N₂) into nitrates (NO₃⁻).

How do fertilizers impact the phosphorus cycle?

Fertilizers boost crop growth but can lead to pollution and eutrophication when they run off into water bodies.