Muscular dystrophy affects the functioning of skeletal muscle. As this disease advances, it can impair the contraction of the diaphragm and the muscles of the rib cage. What effect will this have on the ability of people with this disease to carry out gas exchange?

-It will decrease the ability to exhale but the ability to inhale will be unaffected.
-It will decrease their ability to exchange air into and out of the lungs, decreasing gas exchange.
-It will have no effect on their ability to carry out gas exchange.
-It will cause a buildup of mucus in their respiratory tract, decreasing gas exchange.
-It will lower the surface area for gas exchange, decreasing gas exchange.

Which of the following shows the correct order in which light information travels through the eye? (2 points) lens, pupil, retina, optic nerve pupil, lens, retina, optic nerve pupil, lens, optic nerve, retina lens, pupil, optic nerve, retina

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

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen