Biogeochemical Cycles Flashcards

The biosphere encompasses all regions of Earth where living organisms exist, including land, water, and the atmosphere.
Biogeochemical cycles involve the movement of essential elements like water, carbon, oxygen, and nitrogen through both living (biotic) and nonliving (abiotic) components of an ecosystem.

Precipitation refers to any form of water (rain, snow, sleet) that falls from the atmosphere to the Earth's surface, replenishing water sources.
Transpiration is the process where plants release water vapor into the atmosphere from their leaves, contributing to the water cycle.
Percolation is the movement of water through soil and rock layers, helping to filter and replenish groundwater supplies.
Groundwater is water stored beneath the Earth's surface in soil pores and rock formations, integral for maintaining ecosystems and human consumption.

Photosynthesis is a critical plant process that harnesses solar energy to transform carbon dioxide into carbohydrates, providing food for the base of the food chain.
Carbon fixation is the conversion of inorganic carbon (like carbon dioxide) into organic molecules (like sugars), essential for building biomass in plants.
Cellular respiration is used by living organisms to extract energy from carbohydrates, producing carbon dioxide as a byproduct and returning it to the atmosphere.
Combustion refers to the burning of organic materials and fossil fuels, which releases carbon dioxide and contributes to atmospheric changes.

Nitrogen-fixing bacteria convert atmospheric nitrogen gas into ammonia, making nitrogen available to plants in a usable form.
Nitrogen fixation is the overall transformation of nitrogen gas into ammonia, essential for life as it forms the basis for amino acids and nucleic acids.
Nitrification is a two-step process that converts ammonia into nitrites and then nitrates, which are also usable by plants.
Decomposers, including bacteria and fungi, play a crucial role in breaking down dead organisms, cycling nutrients, and replenishing nitrogen in the soil.
Denitrification is the conversion of nitrates back to nitrogen gas, returning it to the atmosphere and completing the nitrogen cycle.