Question:
Use evidence from the fact that ecological succession means entire communities in an ecosystem change over time to answer the following question. "Which of the following is an example of ecological succession?"

Answer:
Trees, insects, and birds in a forest grew from wildfire-ravaged lands

Question:
Use evidence from the fact that the circulatory system transports blood throughout the body to answer the following question. "What makes sure that the tips of your toes have enough of the gas that plants put off?"

Answer:
your circulatory system

Question:
Use evidence from the fact that cutting down trees in a forest causes the number of trees to decrease in that forest to answer the following question. "A decrease in trees may be attributed to"

Answer:
increased chainsaw sales