Ecosystems/Food Webs
Ecological Pyramids
Energy Flow & Matter Cycling
P & CR
100
What do the arrows show in a food web?
The direction of energy flow
100
What is the ultimate source of energy for all food chains/webs?
The sun!
100
What type of organism makes its own food? Use two words.
What type of organism cannot make its own food? Use two words.
Producer/autotroph
Consumer/heterotroph
100
What types of organisms perform photosynthesis?
What types of organisms perform cellular respiration?
Photosynthesis: plants
Cellular respiration: plants and animals
200
Describe the relationships between producers, consumers, and decomposers.
Producer: an organism that makes its own food for energy.
Consumer: an organism that cannot make its own food.
Decomposer: an organism that gets energy by breaking down wastes and dead organisms.
200
Describe the 10% rule. (talk about the 10% and the 90%)
Only 10% of energy moves from one trophic level to the next, the other 90% is used to sustain life or is lost as heat.
200
Which organism is always at the end of every food chain and food web, but is not always pictured?
Decomposers!
200
How does cellular respiration contribute to the carbon cycle?
It releases carbon dioxide into the atmosphere.
300
If the snake population decreased, which two populations would increase as a result? Why?
Birds and frogs—they are losing a predator
300
Where would you expect to find the bulk of biomass in an ecological pyramid? Why would it be a problem if that level was removed?
Producer level. If it was removed, the food web would collapse. Consumers would lose their main source of energy and nutrients.
300
What is the role of decomposers in the cycling of matter?
Decomposers break down dead organic matter and make nutrients available to producers.
300
What is the role of producers in Earth's systems (the four spheres)?
Producers take in carbon dioxide and convert sunlight into energy through photosynthesis
400
Identify an organism that is both a tertiary and quaternary consumer. Describe specifically how.
Leopard seal. Tertiary because it is eating fish (secondary consumer). Quaternary because it is eating seagull and penguin (tertiary consumers).
400
Draw an energy pyramid. Label each level.
Bonus: if there was a fifth level, what is it called?
Fifth level: Quaternary Consumers
400
If the producer level had 40,000 kcal of energy available, how much energy is available at the tertiary consumer level?
Identify two organisms that fall into that trophic level.
40 kcal at the tertiary consumer level.
Owl and snake.
400
What is the relationship between photosynthesis and cellular respiration?
Show evidence (inputs and outputs for each process).
The inputs of one process are the outputs of the other process.
EX: glucose and oxygen are produced by photosynthesis and needed for cellular respiration
500
Describe how three populations might be affected if the herring population is removed from this ecosystem.
Dogfish/cod/seal/tuna: decrease because they lose their prey
Krill/plankton: increase because they lose their predator
500
Explain why an energy pyramid is limited to four or five trophic levels.
Only 10% of energy moves from one trophic level to the next. Because of the large amount of energy loss, there isn’t enough energy left to support many more levels of consumers by the time you reach the fourth or fifth level.
500
Describe the relationship between energy and matter in an ecosystem. You should also mention heat loss and decomposers.
Energy flows in one direction (sometimes lost as heat) while matter is cycled (decomposers break down dead organisms for producers to use).
500
Describe 3 processes that add carbon to the atmosphere. Name 1 that is caused by human activity.
1. cellular respiration
2. ocean waters warming
3. volcanic eruptions
Human activity: burning fossil fuels, deforestation, etc.