Mr. Brown used the model shown below when discussing plant cells with his class. Why did Mr. Brown use a model? A. The model provides a better representation than a real cell .

B. The model is easier to view since real plant cells are very small. O

C. Most plant cells are dangerous and induce a variety of diseases.

D. Real plant cells can only be viewed with a telescope.

Awic dietitian is meeting with a client who has an infant and a young child. the mother says that the young child is a very picky eater and will only eat crackers and juice. the health worker notices that the child's hair is brittle, his nails tear easily, and the skin inside his lower eyelids is very pale. these are all signs of iron deficiency.

Development of new communities in disturbed environments, such as a burned or a clear cut forest, is called

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