Activities

1. Describe how the Sun makes the Earth a living, working system.
   
   
2. Describe how two or more simple machines can work together to create compound machines.

3. Explain how cell organelles work together.
   
   
4. Explain the relationship among living things in an ecosystem.

Answer Key/Rubric

1. The sun provides energy for all living things. It allows plants to undergo photosynthesis. Since the sun helps plants thrive, this in turn benefits animals and humans that feed off the plants. Plants also indirectly benefit carnivores and omnivores since the animals they prey upon are nourished by these plants. The sun provides warmth, and just enough, so the water that exists on our surface is abundant and available (and does not fully freeze or evaporate).
   
   
2. Acceptable responses may include, but are not limited to:

• Bicycle: has a wheel and axel which allows the bike to move, pulleys are found in the braking mechanisms, levers are found in the handlebars and brakes
• Wheelbarrow: has a wheel and axel which allows it to move, and a lever for its handle bars which allows I to be lifted

3. Acceptable responses may include, but are not limited to:

• Nucleus- contains cell’s genetic material, copies genetic material to undergo reproduction
• Ribosomes- make proteins by reading RNA (ribonucleic acid)
• Cell membranes- split into two so the cells can be reproduced, ingest nutrients

4. Acceptable responses include, but are not limited to:

• Plants provide food, shelter, and habitats for animals
• Certain insects and flowers have a relationship of mutualism since the insects get nutrition, and the flowers are pollenated
• Prey provide nutrition for the survival of the predators
• Insects can carry around or scatter seeds which allow for the continuation of plant growth