Problem: Living things need non-living matter as well as energy. What do you think matter is used for? One thing is to build bodies. They also need it to carry out the processes of life. Any non-living matter that living things need is called a nutrient. Carbon and nitrogen are examples of nutrients. Unlike energy, matter is recycled in ecosystems. You can see how in Figure 3.11. Decomposers release nutrients when they break down dead organisms. The nutrients are taken up by plants through their roots. The nutrients pass to primary consumers when they eat the plants. The nutrients pass to higher level consumers when they eat lower level consumers. When living things die, the cycle repeats.

Question: "What do living things need?"

Answer: "Non-living matter"
Answer: yes

Problem: For thousands of years, people have found fossils. The fossils caused curiosity about Earths past. How did these organisms live? What type of world did they live in? Fossils can tell us a lot about Earths history. In ancient times, fossils inspired myths and stories. These stories included tales of monsters and other incredible creatures. What type of creature do you know that could inspire such stories? Of course, dinosaur fossils were once mistaken for dragons bones. Two thousand years ago, people discovered fossils in China. At the time, they were thought to be dragon bones. We know now that these were not bones, but fossils. So what is the difference?

Question: "What were some fossils originally thought to be?"

Answer: "fairies"
Answer: no

Problem: Earth processes have not changed over time. The way things happen now is the same way things happened in the past. Mountains grow and mountains slowly wear away. The same process is at work the same as it was billions of years ago. As the environment changes, living creatures adapt. They change over time. Some organisms may not be able to adapt. They become extinct. Becoming extinct means they die out completely. Some geologists study the history of the Earth. They want to learn about Earths past. They use clues from rocks and fossils. They use these clues to make sense of events. The goal is to place things in the order they happened. They also want to know how long it took for those events to happen.

Question: "If Earths processes do not change, what does?"

Answer: "Environment"
Answer:
yes