Food Systems 1 Flashcards
What happens in the root nodules of legumes during biological fixation?
Rhizobium bacteria split molecular nitrogen (N₂) into two free nitrogen atoms, which combine with hydrogen to form ammonia (NH₃).
Which bacteria are commonly involved in biological nitrogen fixation?
Symbiotic bacteria like Rhizobium, free-living aerobic bacteria like Azotobacter, anaerobic bacteria like Clostridium, and photosynthetic Cyanobacteria.
What is Soil Formation?
The process by which soil is created from parent rock material through weathering and organic matter accumulation.
What is Soil Composition?
The mixture of minerals, organic matter, air, and water in soil.
What is Soil Erosion?
The removal of the top layer of soil by water, wind, or human activity.
What is Soil Conservation?
Strategies and techniques used to prevent soil erosion and maintain fertility.
What are Biological Populations?
Groups of individuals of the same species living in a specific area.
What are Species Interactions?
Relationships between species such as predation, competition, and mutualism.
What is Photosynthesis?
The process by which plants convert sunlight, water, and carbon dioxide into oxygen and glucose.
What are Food Webs?
Interconnected food chains showing the energy flow through an ecosystem.
What are Ecological Pyramids?
Diagrams representing the relative amounts of energy, biomass, or numbers of organisms at each trophic level.
What is Biodiversity?
The variety of life in an ecosystem, including species, genetic, and ecosystem diversity.
What is the Carbon Cycle?
The process by which carbon is exchanged among the atmosphere, oceans, soil, and organisms.
What is the Nitrogen Cycle?
The movement of nitrogen through the atmosphere, soil, and living organisms, including processes like nitrogen fixation and denitrification.
What is the Conservation of Matter?
A principle stating that matter cannot be created or destroyed, only transformed.
What are the Impacts of Population Growth?
Effects such as increased demand for resources, habitat destruction, and food insecurity.
What is the Green Revolution?
A period marked by increased agricultural production due to high-yield crop varieties and advanced farming techniques.
What is Genetic Engineering?
The modification of an organism’s genetic material to achieve desired traits.
What is Deforestation?
The clearing of forests for agriculture, logging, or urban development.
What is Irrigation?
The artificial application of water to soil for crop growth.
What is Sustainable Agriculture?
Farming practices that maintain productivity while minimizing environmental damage.
What is Integrated Pest Management (IPM)?
A pest control strategy combining biological, cultural, physical, and chemical tools.
What is Overgrazing?
The excessive feeding of livestock on vegetation, leading to land degradation.
What is Desertification?
The process by which fertile land becomes desert due to drought, deforestation, or inappropriate agriculture.
What is the Tragedy of the Commons?
A situation where individuals overuse a shared resource, leading to its depletion.
What is Water Pollution?
Contamination of water bodies by harmful substances such as chemicals, waste, and pathogens.
What is Cultural Eutrophication?
Nutrient enrichment of water bodies caused by human activities, leading to algal blooms and oxygen depletion.
What is Groundwater Pollution?
Contamination of underground water sources by pollutants like pesticides and industrial waste.
What is the Clean Water Act?
U.S. legislation aimed at reducing water pollution and protecting water quality.
What is Habitat Loss?
The destruction of natural environments due to human activities such as urbanization and agriculture.
What are Introduced Species?
Non-native species introduced to an ecosystem, often causing ecological harm.
What are Endangered Species?
Species at risk of extinction due to habitat loss, hunting, or other factors.
What is Conservation?
Efforts to preserve biodiversity and protect natural resources.
What is Decomposition?
Organic matter is broken down by decomposers, releasing nutrients into the atmosphere, soil, and water.
What is Combustion?
Burning of fossil fuels and biomass releases carbon dioxide into the atmosphere.
What happens during Sedimentation and Burial?
Elements like carbon and phosphorus are stored in sediments and (carbon in fossil fuels) over geological timescales.
What is Nitrogen Fixation?
Atmospheric nitrogen (N₂) is converted into ammonia (NH₃) by bacteria or industrial processes.
What is Nitrification?
Conversion of ammonia into nitrites (NO₂⁻) and then nitrates (NO₃⁻) by bacteria.
What is Assimilation?
Plants absorb nitrates and ammonium ions to form proteins and nucleic acids.
What is Ammonification?
Organic nitrogen is converted back into ammonia by decomposers.
What is Denitrification?
Nitrates are converted back into nitrogen gas (N₂) by bacteria, returning it to the atmosphere.
What is Weathering?
Rocks containing phosphorus minerals are broken down, releasing phosphate ions into soil and water.
What is the impact of Mining and Fertilizer Use?
Human activities extract phosphorus for agricultural use, altering its natural cycle.
What is evaporation?
Water is converted from liquid to vapor due to solar energy.
What is transpiration?
Water vapor is released from plants into the atmosphere.
What is condensation?
Water vapor cools to form clouds.
What is precipitation?
Water falls back to Earth as rain, snow, sleet, or hail.
What is infiltration?
Water enters the soil and percolates to recharge groundwater.
What is runoff?
Excess water flows over the surface into rivers, lakes, and oceans.
What is deposition?
Sulfur settles from the atmosphere into soils and water.
