Question

post - food web questions
· above is a food chain. draw arrows to show this food chain. check boxes once you complete tasks.
· explain the direction of the arrows in food chains and food webs.
complete and answer the following to fill out the energy pyramid to the right.
· place the common names of each of the organisms in the food chain above into the grey rectangles.
· number the trophic levels in the white circles.
· label each organism’s role in the food chain in the white rectangles (producer, primary consumer → tertiary consumer).
· which group are herbivores? which trophic level is this?
· which group can capture the sun’s energy and convert it into glucose? what is this process called? which trophic level is this?
· who is the apex predator of the pond ecosystem?
· what do the squiggly arrows to the right side of the pyramid represent? what percent of the energy is lost as this? % explain how this relates to the shape of the energy (and biomass) pyramid.
· what percent of energy is transferred from trophic level to trophic level? % if the algae captured 648.45 kcal of energy through photosynthesis, how much will be transferred to each trophic level? write your answers in the star shapes.
· “energy flows and matter cycles.”
· name 1 detritovore in the pond food web:
· name 1 decomposer from the food web:
· if we added more organism to the pond ecosystem, would the ecosystem become stronger or weaker? explain your reasoning.
· make an argument about why the removal of the following group of organisms would have serious consequences for the pond ecosystem:
producers
decomposers
top predators

Explanation:

Step1: Draw arrows in food - chain

Draw arrows from the organism being eaten to the organism that eats it. For example, if algae are eaten by a small invertebrate, the arrow goes from algae to the invertebrate. This shows the direction of energy flow.

Step2: Explain arrow direction

The arrows in food - chains and food - webs point from the prey to the predator. This indicates the direction of energy transfer as one organism consumes another.

Step3: Fill energy pyramid

Place the organism names in the grey rectangles according to their position in the food - chain. Number the trophic levels in the white circles starting from 1 at the bottom (producers). Label the organism's role (producer, primary consumer, etc.) in the white rectangles.

Step4: Identify herbivores

Herbivores are primary consumers. They eat producers. In a pond ecosystem, small invertebrates that eat algae are often herbivores. This is the primary consumer trophic level.

Step5: Identify energy - capturing group

Producers (like algae) can capture the sun's energy and convert it into glucose through photosynthesis. This is the first trophic level.

Step6: Identify apex predator

The apex predator is the top - level consumer in the food - chain. In a pond, it could be a large fish that has no natural predators within the pond ecosystem.

Step7: Explain squiggly arrows

The squiggly arrows on the right side of the pyramid represent energy loss. Approximately 90% of the energy is lost as heat, waste, and other non - usable forms between trophic levels. This is why the energy (and biomass) pyramid is wider at the bottom and narrower at the top, as there is less energy available at higher trophic levels.

Step8: Calculate energy transfer

Only about 10% of the energy is transferred from one trophic level to the next. If algae captured 648.45 kcal of energy, 64.845 kcal would be transferred to the primary consumers, 6.4845 kcal to the secondary consumers, and 0.64845 kcal to the tertiary consumers.

Step9: Name detritivore and decomposer

A detritivore could be a water flea that feeds on dead organic matter. A decomposer could be bacteria that break down dead organisms in the pond.

Step10: Analyze ecosystem change

Adding more organisms could make the ecosystem stronger if they fill new niches and increase biodiversity. However, if they out - compete existing organisms or introduce new diseases, it could weaken the ecosystem.

Answer:

For drawing arrows: Arrows from prey to predator.
For arrow direction explanation: Points from prey to predator for energy transfer.
For energy pyramid: Fill with organism names, trophic levels, and roles as described.
For herbivores: Primary consumers, e.g., small invertebrates eating algae.
For energy - capturing group: Producers through photosynthesis, first trophic level.
For apex predator: A large fish in the pond with no natural predators.
For squiggly arrows: 90% energy loss, related to pyramid shape.
For energy transfer: 10% transfer, calculations as above.
For detritivore and decomposer: Detritivore like water flea, decomposer like bacteria.
For ecosystem change: Could be stronger or weaker depending on factors.