Question

highlight the correct response.

1. how much energy is transferred from one trophic level to the next?

a. 90% of the energy
b. 50% of the energy
c. 10% of the energy
d. 1% of the energy

1. why must tertiary consumers eat more food than primary consumers?

a. they are larger in size.
b. they need more nutrients.
c. to compensate for decreased energy availability.
d. to maintain body temperature.

1. what does the base of an energy pyramid represent?

a. the primary consumers
b. the secondary consumers
c. the producers with the most energy
d. the producers with the least energy

1. why are food chains limited in length?

a. producers become too large.
b. energy transfer is inefficient.
c. there are not enough consumers.
d. there are too many top - level predators.

1. which statement about energy pyramids is correct?

a. the top level has the most energy.
b. the bottom level has the most energy.
c. all levels have equal amounts of energy.
d. energy is not transferred between levels.

1. how much food must a tertiary consumer eat compared to a primary consumer?

a. 50 times more
b. 75 times more
c. 100 times more
d. 1000 times more

1. what does the size of each level in an energy pyramid represent?

a. the number of organisms
b. the physical size of organisms
c. the amount of available energy
d. the number of species

1. which trophic level has the largest population size?

a. tertiary consumers
b. secondary consumers
c. primary consumers
d. producers

1. what happens to 90% of the energy at each trophic level?

a. it is stored for later use.
b. it is transferred to the next level.
c. it is lost as heat.
d. it is recycled in the ecosystem.

Explanation:

1. Question: How much energy is transferred from one trophic level to the next?

• Answer: 10% of the energy.
• Explanation: In an ecosystem, typically only about 10% of the energy available at one trophic - level is transferred to the next trophic level. This is known as the 10 - percent rule. The rest of the energy is lost as heat during metabolic processes.

1. Question: How much food must a tertiary consumer eat compared to a primary consumer?

• Answer: 1000 times more.
• Explanation: Since only about 10% of energy is transferred between trophic levels, if a primary consumer is at the second trophic level and a tertiary consumer is at the fourth trophic level, going from the primary consumer to the tertiary consumer, there are two energy - transfer steps. So, if we assume the energy transfer is 10% each time, a tertiary consumer needs to eat \(10\times10\times10 = 1000\) times more food compared to a primary consumer to get the same amount of energy.

1. Question: Why must tertiary consumers eat more food than primary consumers?

• Answer: To compensate for decreased energy availability.
• Explanation: As energy is transferred from one trophic level to the next, only a small fraction (about 10%) is passed on. Tertiary consumers are at higher trophic levels, so there is less energy available to them compared to primary consumers, and they need to eat more to meet their energy requirements.

1. Question: What does the base of an energy pyramid represent?

• Answer: The producers with the most energy.
• Explanation: The base of an energy pyramid represents the producers (such as plants) which capture energy from the sun through photosynthesis. They have the most energy available in an ecosystem because they are the starting point of the energy flow.

1. Question: Why are food chains limited in length?

• Answer: Because of the loss of energy between trophic levels.
• Explanation: With each transfer of energy from one trophic level to the next, a large amount of energy (about 90%) is lost as heat. So, after a few trophic levels, there is not enough energy left to support a large number of higher - level consumers, thus limiting the length of food chains.

1. Question: Which statement about energy pyramids is correct?

• Answer: The pyramid shape shows the decrease in available energy at each higher trophic level.
• Explanation: Energy pyramids are wide at the base (where producers are) and narrow at the top (where top - level consumers are) because the amount of available energy decreases as we move up the trophic levels due to energy losses during transfer.

1. The 10 - percent rule of energy transfer between trophic levels is a well - known concept in ecology.
2. Energy loss between trophic levels leads to higher - level consumers needing to consume much more food.
3. Decreased energy availability at higher trophic levels requires tertiary consumers to eat more.
4. Producers form the base of the energy pyramid as they have the most energy.
5. Energy loss limits the length of food chains.
6. The shape of an energy pyramid reflects the decrease in available energy at higher trophic levels.

Answer:

1. 10% of the energy
2. 1000 times more
3. To compensate for decreased energy availability
4. The producers with the most energy
5. Because of the loss of energy between trophic levels
6. The pyramid shape shows the decrease in available energy at each higher trophic level