A river food chain works as follows:
Algae → insects → salmon → bears
The producers in the ecosystem produce 8,000,000 kilocalories of energy via photosynthesis. The bears need 100 kilocalories to survive. Can the ecosystem support the bears, and if so, how many individuals?
(1 point)
Responses
no, 0.8 individuals
no, 0.8 individuals
yes, 800 individuals
yes, 800 individuals
no, 0 individuals
no, 0 individuals
yes, 80 individuals
To answer this question, we need to use the 10% rule in ecology. The rule states that only 10% of the energy from one level of the food chain is transferred to the next level. Therefore, if the algae produce 8,000,000 kilocalories of energy, then the insects can only use 10% of that energy, which is 800,000 kilocalories. The salmon can only use 10% of the energy from the insects, which is 80,000 kilocalories. Finally, the bears can only use 10% of the energy from the salmon, which is 8,000 kilocalories.
Since the bears need 100 kilocalories to survive, the ecosystem can support 80 individuals (8,000/100). Therefore, the answer is yes, 80 individuals.
Yes, the ecosystem can support 80 individuals! Just bear with me, sorry for the pun, but let me explain. The 8,000,000 kilocalories of energy produced by the producers can support a total of 80 individuals, each needing 100 kilocalories to survive. So, 800,000/100 = 80 individuals. Hats off to the river food chain for being able to bear the responsibility!
To determine if the river ecosystem can support the bears, we need to calculate the energy flow through each trophic level.
1. The producers (algae) produce 8,000,000 kilocalories of energy.
2. The insects consume a portion of the energy produced by the algae and pass some of it onto the next level. Let's assume they pass on 10% of the energy they consume.
3. The salmon consume the insects and again pass on 10% of the energy they consume.
4. Lastly, the bears consume the salmon, passing on 10% of the energy they consume.
Let's calculate the energy available to the bears:
First trophic level: 8,000,000 kilocalories (producers)
Second trophic level: 8,000,000 x 0.10 = 800,000 kilocalories (insects)
Third trophic level: 800,000 x 0.10 = 80,000 kilocalories (salmon)
Fourth trophic level (bears): 80,000 x 0.10 = 8,000 kilocalories
Since bears need 100 kilocalories to survive, we can divide the available energy by the energy required:
8,000 kilocalories ÷ 100 kilocalories = 80 individuals
Therefore, the ecosystem can support 80 bear individuals.
The correct response is:
yes, 80 individuals
To determine if the ecosystem can support the bears and how many individuals it can sustain, we need to calculate the available energy at each trophic level.
Given the food chain:
Algae → insects → salmon → bears
We know that the producers, which are the algae, produce 8,000,000 kilocalories of energy via photosynthesis.
In a typical ecosystem, the flow of energy from one trophic level to the next is about 10%. This means that only 10% of the energy is transferred from one level to the next.
First, let's calculate the energy available at the insect level. Since only 10% of the energy is transferred to the next level, the insects will have 10% of the energy produced by the algae, which is:
10% of 8,000,000 kilocalories = 800,000 kilocalories
Now, let's calculate the energy available at the salmon level. Again, only 10% of the energy is transferred, so:
10% of 800,000 kilocalories = 80,000 kilocalories
Finally, let's calculate the energy available at the bear level. Again, only 10% of the energy is transferred, so:
10% of 80,000 kilocalories = 8,000 kilocalories
Since each bear needs 100 kilocalories to survive, we divide the available energy by the energy needed per bear:
8,000 kilocalories / 100 kilocalories = 80 bears
Therefore, the ecosystem can support 80 bear individuals. The correct answer is "yes, 80 individuals."