Nutrient cycles
All life on earth requires water to live, and it makes up the majority of __________ ____________.
living cells
What would most likely happen to plant growth if nitrogen-fixing bacteria were eliminated from an ecosystem?
Plant growth would significantly decrease
What is a food web?
A model of energy flow in an environment showing many food chains that interact and overlap.
What type of organism, predator or prey, removes the weak or sick to control population size?
Predators remove weak or sick prey, controlling prey population size!
If a drought occurs in an ecosystem, which limiting factor is most directly affected?
Water availability
What do the water, oxygen, and nitrogen cycles all have in common?
All of these substances are in limited quantity on Earth, so they are cycled by design to provide what is needed by living organisms.
Photosynthesis, cellular respiration, and simple combustion reactions drive which cycle?
The Carbon Cycle
Organisms that eat both plants and animals are called _________.
omnivores
Why does the predator population never reach the same maximum size as the prey population?
Predators are higher on the trophic pyramid and need more prey to support their numbers
Both species benefit from the interaction this is a form of symbiotic relationship known as ______________.
mutualism
What is the correct term for the process by which plants release water vapor through their leaves?
transpiration
Which of the following enters the carbon cycle as a by-product or waste product of cellular respiration?
Carbon dioxide
Producers are also called_______________.
autotrophs
True or false
In a population graph of predators and prey over several years both populations steadily increase.
False
Predator population rises after prey population rises, then both fall cyclically.
What might happen if two different species share the exact same niche in an ecosystem?
One species may out-compete the other, possibly causing its decline or extinction
What is so unusual about nitrogen in the atmosphere?
Although 78% of the earth's atmosphere is nitrogen gas, none is usable in atmospheric form.
In the nitrogen cycle, what process converts organic nitrogen in dead organisms back into inorganic forms?
Decomposition
The maximum number of individuals an environment can support is known as its ______________.
carrying capacity
When adaptations occur in a population, what is actually changing?
The population's gene pool shifts as advantageous genes are passed to offspring
What is the difference between intraspecific and interspecific competition?
Intraspecific is competition within the same species; interspecific is between different species
List the 4 steps of the nitrogen cycle
nitrogen fixation
ammonification
nitrification
assimilation
What are the three main drivers of the carbon cycle?
photosynthesis
cellular respiration
combustion
Label the parts of this food chain by matching the organism and their role:
The sun provides the energy for grass to grow. A grasshopper eats the grass. A bird swoops down and eats the grasshopper. A bobcat captures and eats the bird. Mushrooms break down the remains of the bobcat when it dies.
grass- producer
grasshopper- primary consumer
bird- secondary consumer
bobcat- tertiary consumer
mushrooms- decomposer
When was predation established and why?
After Noah's Flood, when God allowed animals to be food for others
How does commensalism differ from parasitism?
In commensalism, one benefits and the other is unaffected; in parasitism, one benefits and the other is harmed