The cell membrane is composed of a phospholipid bilayer. Because it is made of lipids, they are non-polar molecules. That means that other non-polar molecules can easily pass through. In addition to other non-polar molecules, small, uncharged molecules like water, glycerol, ethanol can also pass through without the use of channel or carrier proteins. <span />
Answer:
with each heartbeat,the heart pumps blood throughout our bodies,carrying oxygen to every cell,after delivering oxygen the blood returns to the heart the heart then sends the blood to the lungs to pick up more oxygen.
As means of locomotion, bacteria possess flagella.