Food Chains
What do arrows in a food chain represent?
Flow of energy
What is the ultimate source of energy in most ecosystems?
→ The Sun
Define symbiosis.
Close relationship between species
What is deforestation’s effect on ecosystems?
Loss of habitat, biodiversity
Define abiotic factor.
Non-living part of ecosystem
Give an example of a primary consumer.
Grasshopper, zooplankton, rabbit
About what percentage of energy is transferred from one trophic level to the next?
~10%
Give an example of mutualism.
Clownfish & anemone, cleaner fish & shark
What does overfishing do to aquatic food webs?
Removes key species, imbalance
Define niche.
Role an organism plays
Which level of the food chain has the most energy available?
Producers
What happens to the other 90% of energy?
Lost as heat, movement, respiration
What’s the difference between commensalism and parasitism?
Commensalism = one benefits, other neutral; Parasitism = one benefits, other harmed
Give one example of an invasive species and its effect.
Zebra mussels clog water pipes and outcompete native mussels.
Lionfish in coral reefs eat large numbers of juvenile fish, reducing biodiversity.
Define biomass.
Total mass of living matter
What’s the difference between a food chain and a food web?
Chain = one path, Web = many connections
Which type of pyramid best shows energy transfer?
Energy pyramid
Intraspecific vs. interspecific competition?
Intra = same species; Inter = different species
What is eutrophication and what causes it?
Nutrient overload → algae blooms
Define carrying capacity.
Max population an environment supports
Why are top predators most affected by biomagnification?
Toxins build up higher in the chain
Why are energy pyramids usually limited to 4–5 trophic levels?
Energy runs out
What is a keystone species and why are they important?
Species critical to ecosystem balance
Why is biodiversity important for ecosystem stability?
It increases resilience
Define ecological succession.
Gradual change in ecosystems over time