Vocabulary
what is ecosystem
An ecosystem is a community of living organisms (plants, animals, microbes) interacting with their non-living environment (air, water, soil). Its balance is crucial because every part relies on others; disrupting one element, like removing a predator or polluting a river, can cause a cascade effect, harming the entire system, impacting resources, and threatening species survival.
How do human activities significantly alter the carbon cycle, and what are the consequences?
Burning fossil fuels (coal, oil, gas) releases vast amounts of stored carbon as CO2 into the atmosphere, while deforestation reduces trees that absorb CO2. This excess atmospheric carbon traps heat, causing global warming and climate change, and contributes to ocean acidification as oceans absorb more CO2.
What limits a population's growth in a stable environment?
Carrying Capacity (K), the maximum population size an environment can sustain indefinitely due to environmental resistance, which includes density-dependent factors (like food, space, disease, predation) and density-independent factors (like floods, fires, climate)
Organism
An individual living thing.
What percentage of the Earth's surface is covered by water?
Approximately 71% of the Earth's surface is covered by water.
what is biodiversity
Biodiversity refers to the variety of life on Earth, from genes to species to ecosystems. Loss of biodiversity means the reduction or extinction of species, often due to habitat destruction or climate change, weakening ecosystems' resilience and ability to provide essential services like clean air and water.
What is the role of bacteria in the nitrogen cycle, and why is it crucial
Bacteria perform vital steps like nitrogen fixation (converting atmospheric nitrogen gas into usable ammonia) and nitrification (converting ammonia to nitrates). Without these bacteria, plants couldn't get the nitrogen needed for proteins and DNA, disrupting the foundation of food webs.
How does population density affect disease spread?
High density increases the impact of density-dependent factors, like infectious diseases, as pathogens spread faster in crowded conditions, potentially causing rapid population decline, as seen with fungal blight in crops.
Population
All organisms of the same species in an area.
Which gas is primarily responsible for global warming?
Carbon dioxide CO2 cap C cap O sub 2) is the main greenhouse gas causing global warming
what is sustainability
Sustainability means meeting present needs without compromising future generations' ability to meet their own. It involves using resources wisely, reducing waste, protecting ecosystems, and adopting practices like renewable energy to ensure long-term environmental health.
Why is the phosphorus cycle considered a "sedimentary cycle," and what does this mean for ecosystems?
Unlike the carbon or nitrogen cycles, phosphorus primarily cycles through rocks, soil, and water (sediments) and has no significant atmospheric component. This means its movement is slower, often limited by slow geological weathering, and disruptions (like fertilizer runoff) can quickly cause rapid over-enrichment (eutrophication) in water bodies.
What are the differences between r-selected and K-selected species?
R-selected species (like rats) have high reproductive rates and many offspring, thriving in unstable environments, while K-selected species (like elephants) have few offspring, slower growth, and better suited for stable environments near carrying capacity.
Community
All different populations (species) in an area.
What is the largest rainforest in the world?
The Amazon Rainforest is the world's largest rainforest.
what is carbon footprint
Your carbon footprint is the total greenhouse gases (like carbon dioxide) emitted by your activities (driving, energy use, consumption). Reducing it by using less energy, choosing public transport, or eating local food lessens your contribution to climate change and global warming.
What is the primary driver of the water cycle (hydrologic cycle), and how do humans impact it?
The Sun's energy drives the water cycle through evaporation. Humans impact it by altering land use (deforestation affects transpiration), building dams, extracting groundwater, and contributing to climate change, which alters precipitation patterns, leading to droughts or floods.
How does age structure influence future population growth?
A population with a large proportion of young, pre-reproductive individuals (a wide base in an age pyramid) indicates future growth, while a population with many older individuals suggests potential decline, impacting future workforce and resource needs
Ecosystem
Living (biotic) and non-living (abiotic) factors in an area.
Which international agreement aims to combat climate change?
The Paris Agreement is a global accord to address climate change.
what is Pollution
Pollution introduces harmful substances or energy into the environment, damaging ecosystems and health. Types include air pollution (factory emissions), water pollution (plastic, chemicals in rivers), soil contamination (pesticides), and noise pollution, all leading to habitat loss, species harm, and health problems.
How do decomposition and cellular respiration link the carbon, nitrogen, and phosphorus cycles?
When organisms die, decomposers (bacteria, fungi) break them down, releasing carbon, nitrogen (as ammonia/nitrates), and phosphorus back into the soil and water. Animals obtain these elements by eating plants or other animals, while cellular respiration by all living things releases carbon back as CO2, demonstrating the interconnected recycling of these elements.
How does human development affect population growth (Demographic Transition)?
As countries develop (reduce poverty, improve education/women's status, healthcare), birth rates fall, leading to slower population growth, shifting from high birth/death rates to low birth/death rates, a process called demographic transition.
Biome
Large regions with similar climate and dominant plant life (e.g., desert, rainforest).
Which microorganism acts as a biological indicator for sulfur dioxide pollution?
Lichens are sensitive to sulfur dioxide and serve as bioindicators, reflecting pollution levels.