What part of the cell surrounds the cytoplasm of the cell and is responsible for controlling traffic going into/out of the cell?

Is it considered muscle s ennervation if sympathetic fibers innervate the vessels within the muscle?

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

Why do leaves change color in the fall? green pigments break down and no longer mask the color of chlorophyll. chlorophyll breaks down and no longer masks the colors of other pigments. red- and yellow-colored pigments grow and mask green-colored chlorophyll. green-colored chlorophyll breaks down and turns red and yellow.