The following systems help the body get oxygen and remove carbon dioxide waste. Apply what you learned about the heart to order these systems from the simplest to the most complex.

What do lava flows made of aa indicate about the type of volcanic eruption that occurred? a. the eruption was viscous. b. the eruption was pyroclastic. c. the eruption was explosive. d. the eruption was quite. !

1. emigration the movement of people from one place to another 2. immigration a situation in which resources are being used up at a faster rate than they can be replenished 3. migration the leaving of one's homeland to settle in a new place 4. overpopulation the movement of people to a new country 5. sustainable development a situation in which the birth rate is not sufficient to replace the existing population 6. underpopulation the ability to meet current needs without reducing the ability to meet future needs 7. unsustainable development the increase in the population of a city 8. urbanization a situation in which the number of people exceeds the available natural resources in an area

Text version using the diagram above, match the description to the corresponding location in the carbon cycle model. provide the letter only. carbon dioxide is converted to sugar used for food. carbon trapped in fossil fuels is converted to carbon dioxide. organic carbon is converted to fossil fuels. carbon dioxide is converted to carbonates. sugar is broken down and converted to carbon dioxide. location location location location location