Which of the following best summarizes the function of the respiratory system?
a. to transport oxygen to cells and wastes away from cells.
b. to protect the organs in the chest cavity
c. to move oxygen from the air into the body and carbon dioxide from the body into the air
d. to provide a barrier between the body and the environment
c** which of the following is not true about the structure of an alveolus?
a. it has thick walls to trap gases that enter during breathing.
b. it has high surface area to allow lots of gas exchange.
c. it has a high concentration of oxygen and a low concentration of carbon dioxide.
surface mining destroys mountain tops, landscapes, forests and wildlife habitats. on top of that, it leads to soil erosion and destruction of agricultural land. the landscape changes can also disrupt river channels and streams, which leads to flooding. which, can destroy plant life and other animals as well.
for example, forests have higher evapotranspiration than other ecosystems, such as grasslands, because of their deeper roots and greater leaf area. thus forests have a net moistening effect on the atmosphere and become a moisture source for downwind ecosystems.
a. to transpor...