| mitochondria | smooth outer membrane and a folded inner membrane. uses energy from glucose for aerobic respiration. |
| What does the energy released by respiration end up in? | molecules of ATP (adenosine triphosphate) |
| How is ATP used in a cell? | to provide energy for muscle contraction, active transport and building large molecules |
| cell wall | rigid and provides support for the cell. consists of bundles of long, straight cellulose molecules that lay side by side to form microfibrils. |
| cell surface membrane | double layer of phospholipid molecules tightly packed together. bigger protein molecules are embedded in the phospholipid molecules either half way through or all the way in. it is also partially permeable. |
| diffusion | particles will diffuse through the cell membrane from a high concentration to a low concentration as long as they are small enough to pass through the very small gaps between the phospholipid molecules eg. water, oxygen and co2 |
| osmosis | movement of water molecules across a partially permeable membrane from a high to low concentration. concentration of water molecules is known as water potential |
| facilitated diffusion | glucose and many other water soluble molecules are too big to diffuse across the membrane by themselves, they must be helped across by carrier proteins. each substance has its own specific carrier protein. |
| glucose in facilitated diffusion | glucose fits on the outside end if a glucose carrier protein this causes the protein to change shape allowing the glucose molecule to diffuse through it into the cytoplasm of the cell. |
| how do mineral ions diffuse through the cell | they have electrical charges on them so specific channel proteins in the membrane allow them to diffuse through |
| active transport | the substance fits into a specific carrier protein then molecules of ATP provide energy to change the shape of the protein, as it changes shape the protein actively transports the substance across the membrane . |
