Title: Lesson: What food gives you the most energy?
Course: 2024 Science 6° > Section: 17 March - 23 March

Review this lesson to learn how the energy flows and the role different organisms play in a food chain.

Roles in the Ecosystem

Watch the video and answer the questions.

Autotrophic / Producers

All organisms have a role in each ecosystem.

Organisms that produce their own food are called producers. They are also called Autotrophic organisms because they use light for photosynthesis.

Heterotrophic / Producers

Heterotrophic organisms are those which obtain their nutrients from autotrophic or other heterotrophic organisms. They are called consumers because they do not produce their own food. There are many types of consumer:

1. Herbivores eat producers directly. These animals break down the plant structures to get the materials and energy they need.

2. Carnivores eat animals; they can eat herbivores or other carnivores.

3. Omnivores eat plants and animals as well as fungi, bacteria, and organisms from the other kingdoms.

4. Scavengers,  is an organism that mostly consumes decaying biomass, such as meat or rotting plant material. Many scavengers are a type of carnivore, which is an organism that eats meat. While most carnivores hunt and kill their prey, scavengers usually consume animals that have either died of natural causes or been killed by another carnivore.

5. Parasites. They feed on other animals without killing them. They can live inside or outside the body. Examples: ticks and fleas.

Question 1

Match the type of consumer to its correct definition

- Very good!!
- Review your answers
- They consume waste and dead animals, or carrion. Examples: vultures, hyenas, and some types of beetles.
Feedback: Scavengers
- They feed on other animals without killing them. They can live inside or outside the body. Examples: ticks and fleas.
Feedback: Parasites
- They eat plants, leaves, flowers, fruit, pollen, nectar, seeds, and roots. Examples: butterflies, termites, and elephants.
Feedback: Herbivores
- They feed on other animals. Examples: praying mantis, lions, and tigers.
Feedback: Carnivores
- They consume animals and plants: pigs, foxes, dogs, and human beings.
Feedback: Omnivores

Life on Earth Flow of Energy in Ecosystems

We eat to supply energy to our bodies. We obtain energy from food with the help of oxygen. Therefore, sunlight is vital to obtain energy, since sunlight is a key part of photosynthesis, the process in which autotrophic organisms produce oxygen. Energy from autotrophic organisms flows to consumer organisms, and this energy flows to other consumer organisms when they are eaten. So, in every ecosystem, energy is constantly flowing from producers to consumers and eventually back to producers.

A trophic chain, or food chain helps us understand how energy and matter flow among the organisms.

- -Energy is transferred from one trophic level to another.

- -Energy can only flow through the ecosystem in one direction.

- -At each trophic level organisms need sufficient energy to heat themselves and reproduce, therefore only ten percent of the energy in each level is transferred to the next higher level.

- -Since only ten percent of the energy in a level is transferred to the next, most energy pyramids do not have more than 5 energy levels.

- -Animals in higher trophic levels tend to be larger.

Watch the video to understand how the energy flows.

Food chain

A food chain is as system of organisms that transfer energy from one trophic level to another

Food chain matching exercises

Match the type of consumer to its correct definition.

- Very good!
- Try again!
- They are at the bottom of the food chain. They get their energy through photosynthesis
Feedback: Producer
- Fungi and bacteria that feed on waste and the remains of living things from all trophic levels. They return matter to the soil, making it available again for producers.
Feedback: Decomposers
- Consumers that feed on other consumers and producers, that is, carnivores and omnivores.
Feedback: Secondary consumer
- Consumers that feed on producers, that is, herbivores and omnivores.
Feedback: Primary consumer

Summary

Trophic chains are complex energy cycles that keep biomes going. Some organisms are part of more than one food chain, and other coexist in beneficial relationships.

You reach the end of this lesson!