How does the opening and closing of the stomata help the plant? * A. It aids in releasing turgor pressure from the guard cells.
B. It helps maintain the water pressure within the stroma.
C. It helps to regulate the amount of oxygen that enters the plant.
D. It helps the plants maintain homeostasis by regulating the amount of water the plant loses during transpiration.

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