Question

Why are plants and the bottom of the energy pyramid?

Answer 1

An energy pyramid shows how much energy is flowing through a food chain/web or just a meal. The plants collect energy from the sun, so at the start, they get the most energy. Then, herbivores eat the plants. They still get a good bit of energy, but less so because the plants have already used it to make glucose/their food. Then, predators/carnivores eat the herbivores. They get much less energy because the herbivores have used a lot. The "top" predators get the least energy, because so much of the energy has been used up mostly.

That is also why there are more plants than herbivores, more herbivores than predators, and more predators than "top" predators. Because the top ones get the least energy.

So, the plants are at the bottom because they start the whole eating frenzy, and because they start with the most energy.

Answer 2

What is an energy pyramid?

An energy pyramid is a graphical model that shows energy flow in a community. In this case thought, it shows how energy flows in a biome.

Why do the percents decrease as you get to the top of the pyramid?

The plants at the bottom of the pyramid have the most energy because they are the producers of the biome. They take the sun rays and use photosynthesis to make food and turn that into energy for animals. Herbivores have to move around to find their food. Finding food takes energy so that's why they have less amount of energy. Another reason is because they have to chew and swallow their food. Their digestive system has to use energy to break down the food molecules and get the essential nutrients out of the plant for the herbivore. The carnivore has the least amount of energy because they have to track their prey. Moving around requires a lot of energy. Also by the time the carnivore attacks the herbivore, they're already digesting the energy and nutrients from the plants so there's less of those left.