Name the level of organization each of the following belongs to Bees, butterflies and hummingbirds.

trachea, alveoli, lung capillaries, arteries

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.

condenser is used to focus in the light microscope.