The tiny air sacs at the terminal end of the airways; the place where gas exchange occurs in the lungs

The concept of keystone species is controversial among ecologists because most organisms are highly interdependent. if each of the trophic levels is dependant on all others how can we say one is most important

Describe the function of the endomembrane system? what organelles are involved?

19. a cell is viewed under a microscope and is found to have two nuclear envelopes and spindles that appear to be breaking apart. which phase of mitosis is the cell most likely in? a. metaphase b. prophase c. telophase d. anaphase