Diffusion/Osmosis
Diffusion: movement of any molecule across the membrane from an area of high concentration to low concentration
Osmosis: movement of water from an area of high concentration to low concentration
Facilitated Diffusion: movement of molecules with the additional help of a cell membrane protein
ex: movement of glucose across a transport protein
**All of these are examples of passive transport**
Passive transport-no need for energy
movement of molecules with the concentration gradient (an area of high concentration to low concentration)
Iodine has moved into the semi-permeable membrane (selectively allows only certain molecules to pass through). It has moved from an area of higher concentration (beaker) to an area of lower concentration (inside baggie).
Iodine is an indicator--therefore it changes color when it comes in contact with starch--HENCE the starch turning purple/black inside of the baggie.
Starch cannot move because starch is too large of a molecule. The pores of the baggie are smaller than the size of the starch molecules.
Iodine is an indicator--therefore it changes color when it comes in contact with starch--HENCE the starch turning purple/black inside of the baggie.
Starch cannot move because starch is too large of a molecule. The pores of the baggie are smaller than the size of the starch molecules.