Every organism needs food which provides the energy to live. The movement of energy through an ecosystem can be represented through the Food Chain.

A food chain is made up of several levels:

1. Producers: Plants, algaes. Produce their own food through photosynthesis.

2. Consumers: Obtain the food by eating other living things.

• Primary consumers: herbivores-omnivores. Rabbits, grasshoppers.

• Secondary consumers: Fox, toads… Predators. Carnivores-omnivores.

• Tertiary consumers: Snakes, hawks. Eat secondary consumers.

1. Decomposers: Live on the remains of other living things. Fungi, bacterias.

A food webs occur when many food chains are connected in an ecosystem.

Extinction occurs when every single member of a species dies and none are left alive.

Extinction is often a cultural process and has occurred for millions of years.

There are many natural causes of extinction, however humans are responsible for most of the recent loss of biodiversity in the world. This is a result of several destructive practices and their consequences.

• Climate change.

• Hunting and capturing animals.

• Pollution.

• Over-exploited resources.

• Releasing pets into the wild.

• Alteration of habitats.

Biodiversity is essential for a healthy planet Earth and has a direct impact on our lives.

Endangered species are those which are in danger of extinction. National Parks and Biosphere reserves are created to protect wildlife and its environment.

• The Iberian Lynx and the Iberian Imperial Eagle are the most endangered species in Spain.

• Monfragüe National Park and Doñana National Park are important biodiversity reserves to protect endangered species.

1. Write the definition of Biosphere.

2. Why do organisms need food?

3. What does a food chain represent?

4. In a food chain there are several levels. Could you write them?

5. Explain the producers level.

6. What is the process used by producers to make their food?

7. Explain the consumers.

8. Explain the types of consumers and give examples of them.

9. Explain the decomposers.

10. Design a food chain.

11. Explain with your own words the definition of a food web.

12. When do we talk about extinction?

13. Explain the causes and effects of biodiversity loss.

14. Explain the definition of Endangered species.

15. Why are a National Park or a Biosphere reserve created?

16. What are the most endangered species in Spain? And in Extremadura?

17. Write two examples of National Park or Biosphere reserve in Spain?