Energy Pyramid Worksheet online exercise for - Free Printable

Understanding the Energy Pyramid

The image shows an energy pyramid, which illustrates how energy flows through a food chain or web. As stated, only about 10% of the energy from one trophic level is passed on to the next higher level. The rest is lost as heat due to metabolic processes (like respiration, movement, and digestion).

---

Step-by-Step Solution: Placing Organisms in the Energy Pyramid

We are given the following organisms:

- Producers: Grass, Cattail
- Primary Consumers: Grasshopper, Cricket, Shrew (but note: shrews are omnivores, but they often eat insects like crickets)
- Secondary Consumers: Frog, Snake
- Tertiary Consumers: Hawk

Let’s analyze each organism's role.

---

#### 1. Producers
These are organisms that produce their own food using sunlight via photosynthesis.

✔ Grass and Cattail → Producers
→ Place at the bottom of the pyramid.

---

#### 2. Primary Consumers
These are herbivores that eat producers.

✔ Grasshopper → Eats grass
✔ Cricket → Eats plants (cattails, grass)
✔ Shrew → While shrews can be omnivorous, they often consume insects and small invertebrates, but they may also eat seeds or plant material. However, in most food chains, shrews are considered secondary consumers because they primarily eat insects. But here, we’ll consider crickets and grasshoppers as primary consumers.

So:
- Grasshopper
- Cricket

→ Place these in the second level (Primary Consumers)

> Note: Shrew is not a primary consumer — it eats insects, so it's higher up.

---

#### 3. Secondary Consumers
These animals eat primary consumers.

✔ Frog → Eats insects like crickets and grasshoppers
✔ Snake → Eats frogs, mice, or other small animals

But wait — snakes eat frogs, which are secondary consumers, so snake would be tertiary.

Let’s reconsider:

- Frog → eats crickets/grasshoppers → Secondary Consumer
- Shrew → eats crickets → Secondary Consumer

So:
- Frog
- Shrew

→ Place in Third Level (Secondary Consumers)

---

#### 4. Tertiary Consumers
These eat secondary consumers.

✔ Snake → Eats frogs, shrews, etc. → Tertiary Consumer

→ Place in Fourth Level (Tertiary Consumers)

---

#### 5. Top Predators
These are apex predators that have no natural predators.

✔ Hawk → Eats snakes, frogs, shrews, mice → Top Predator

→ Place in Top Level (Top Predators)

---

✔ Final Placement in the Energy Pyramid:

| Level | Organisms |
|---------------------|-------------------------------|
| Producers | Grass, Cattail |
| Primary Consumers | Grasshopper, Cricket |
| Secondary Consumers | Frog, Shrew |
| Tertiary Consumers | Snake |
| Top Predators | Hawk |

---

🔁 Energy Flow (Arrows)

The arrows on the right side of the pyramid show energy moving upward. Each arrow represents the transfer of ~10% of energy from one level to the next.

So:
- Energy from Grass & Cattail → goes to Grasshopper & Cricket
- Then to Frog & Shrew
- Then to Snake
- Finally to Hawk

Each step loses ~90% of energy.

---

📌 Summary Answer:

Energy Pyramid Organization:

1. Producers: Grass, Cattail
2. Primary Consumers: Grasshopper, Cricket
3. Secondary Consumers: Frog, Shrew
4. Tertiary Consumers: Snake
5. Top Predators: Hawk

This arrangement reflects the flow of energy from the sun → plants → herbivores → carnivores → top predators.

---

💡 Key Concept:

Only 10% of energy transfers between levels. That’s why there are usually fewer organisms at higher levels — there isn’t enough energy to support large populations.

For example:
- A large number of grasses support many crickets,
- Crickets support fewer frogs,
- Frogs support even fewer snakes,
- And only a few hawks can survive at the top.

---

✔ Final Answer:
Place the organisms as follows:

- Bottom (Producers): Grass, Cattail
- Second Level (Primary Consumers): Grasshopper, Cricket
- Third Level (Secondary Consumers): Frog, Shrew
- Fourth Level (Tertiary Consumers): Snake
- Top (Top Predators): Hawk

This completes the energy pyramid!