If an investigation proposes a hypothesis that is impossible to test or measure through experimentation, it is classified as such.
What is not useful (or scientifically invalid)?
This sphere encompasses all living organisms across land, ocean, and atmosphere.
What is the biosphere?
The four main structural layers of Earth, listed in order from the outermost surface to the center.
What are the crust, mantle, outer core, and inner core?
This biogeochemical cycle is unique because it lacks a significant gaseous or atmospheric component.
What is the Nitrogen cycle?
The state of matter water enters when it undergoes evaporation from lakes or oceans.
What is a gas (water vapor)?
In an experiment testing how fertilizer runoff affects algae growth in a pond, the amount of fertilizer added represents this type of variable.
What is the independent variable?
Heavy rainfall eroding topsoil from a hillside into a river is an interaction between these two spheres.
What are the hydrosphere and geosphere?
Tectonic plates pulling apart from one another at ocean ridges form this type of boundary.
What is a divergent boundary?
Specialized soil bacteria convert unusable atmospheric nitrogen (N2) into usable ammonia (NH3) through this process.
What is nitrogen fixation?
Sunlight, air temperature, soil type, and wind are classified as non-living ecosystem components.
What are abiotic factors?
As water temperature rises in an aquatic ecosystem, this key dissolved gas indicator's capacity decreases.
What is dissolved oxygen (DO)?
Ash and toxic gases released into the air during a volcanic eruption represent an interaction between these two spheres.
What are the geosphere and atmosphere?
The San Andreas Fault is a classic example of this boundary type, where plates slide horizontally past one another.
What is a transform boundary?
The biological process that converts nitrates and ammonia back into nitrogen gas, returning it to the atmosphere.
What is denitrification?
Water vapor cooling as it rises to form clouds represents this stage of the water cycle.
What is condensation?
A researcher measures plant growth height in response to differing soil pH levels. Plant growth height is classified as this variable.
What is the dependent variable?
Coastal vegetation absorbing groundwater to perform photosynthesis involves these three spheres.
What are the biosphere, hydrosphere, and geosphere?
This layer of the geosphere is composed primarily of solid iron and nickel under extreme pressure.
What is the inner core?
Carbon moves from the biosphere back into the atmosphere through these two primary processes.
What are cellular respiration and combustion (burning biomass/fossil fuels)?
Decomposers, plants, insects, and animals belong to this ecosystem component group.
What are biotic factors?
Two factors besides temperature that directly affect the amount of dissolved oxygen water can hold.
What are salinity and atmospheric pressure (or water movement/aeration)?
The vast majority (approx. 97%) of Earth's total water volume is stored in this form and place.
What is saltwater in the oceans?
Deep ocean trenches and volcanic mountain ranges are formed at this type of plate boundary where plates collide.
What is a convergent boundary (or subduction zone)?
The primary element backbone abundant in all organic compounds plays a critical role in regulating global climate.
What is carbon?
The process by which moisture is released into the atmosphere from plant leaves.
What is transpiration?