Experimental Design
What is the most likely hypothesis if identical plants receive the same water but different music types and show different heights?
Plants exposed to music will grow taller than others
Which sphere consists of mostly gases surrounding Earth?
Atmosphere
Name the stage of the water cycle where water vapor cools and forms clouds.
Condensation.
Which process converts nitrates back into nitrogen gas released to the atmosphere?
Denitrification.
Which environmental change will increase the amount of carbon removed from the atmosphere:
a forest increasing in size,
a field reducing in size,
a factory replacing a forest,
or a parking lot built on a field?
a forest increasing in size
In the hypothesis “The temperature of the Earth will rise as carbon dioxide is increased in the atmosphere,” identify the dependent variable.
Temperature of the Earth.
Which sphere is the mostly solid, rocky part of Earth?
Geosphere
What stage happens when water falls from the clouds?
Precipitation
In the nitrogen cycle, what is a simplified way nitrogen can travel in the biosphere?
air → bacteria → plants → animals
Which process listed is part of the water cycle: ammonification, condensation, denitrification, or respiration?
condensation
In the hypothesis “The temperature of the Earth will rise as carbon dioxide is increased in the atmosphere,” identify the independent variable.
Presence (concentration) of carbon dioxide.
Which sphere contains all life?
Biosphere
Which process describes water moving downhill into streams and rivers?
Runoff
Which process in the carbon cycle removes carbon dioxide from the atmosphere and stores it in plants?
Photosynthesis.
Most of Earth's water is which type: freshwater, groundwater, salt water, or surface water?
salt water
Why is a control group important in an experiment testing a treatment on diseased plants?
To show results are caused by the treatment and do not happen naturally (i.e., isolate treatment effect).
If a river is winding through vegetation, which two spheres are interacting?
Biosphere and Hydrosphere
Which process involves plants releasing water vapor to the atmosphere?
List two major carbon sinks and two major carbon sources from the carbon cycle.
Sinks — deep ocean sediment, photosynthesis/trees; Sources — combustion, respiration/decay.
Classify these terms as Carbon Sink/Reservoir or Carbon Source: photosynthesis, respiration, combustion, deep ocean sediment.
Photosynthesis — Sink; Respiration — Source; Combustion — Source; Deep ocean sediment — Sink/Reservoir.
Design a one-sentence hypothesis and identify the independent and dependent variables for an experiment testing CO2 concentration effects on plant growth.
Example: Hypothesis — "If CO2 concentration increases, then plant growth will increase." Independent variable — CO2 concentration; Dependent variable — plant growth (height/biomass).
Explain how a volcanic eruption demonstrates interaction between two spheres; name the spheres and describe the interaction in one sentence.
Atmosphere and Geosphere — volcano (geosphere) emits gases and ash into the atmosphere, altering air composition.
Provide the correct definitions for: condensation, precipitation, transpiration, and evaporation
Condensation — water vapor cools to form liquid droplets/clouds; Precipitation — liquid or solid water falling from clouds; Transpiration — plants release water vapor; Evaporation — liquid water becomes vapor from surfaces.
Explain (2–3 sentences) how increased combustion of fossil fuels affects the carbon cycle and one likely ecosystem consequence.
Increased fossil fuel combustion raises atmospheric CO2, increasing greenhouse effect and potentially changing climate patterns; ecosystems may experience altered species distributions and stressed plants.
Define "biogeochemical cycle" in one clear sentence.
A biogeochemical cycle is the movement of chemical elements or compounds through Earth’s biological, geological, and chemical systems (e.g., carbon moving among atmosphere, biosphere, hydrosphere, geosphere).