Channel proteins facilitate the transport of substances across a cell membrane. They do this through the process of either facilitated diffusion or active transport depending on the concentration gradient, or the difference in the concentration of substances inside and outside the cell membrane.

During diffusion, when the concentration of molecules on both sides of a membrane is the same, the molecules will continue to move across the membrane in both directions. 2. An animal cell that is surrounded by fresh water will burst because the osmotic pressure causes water to move into the cell.

Aquaporin is an example of a channel protein in the cell membrane that allows water molecules to flow through. Conversely, carrier proteins do not form channels.

There are two classes of membrane transport proteins—carriers and channels. Both form continuous protein pathways across the lipid bilayer. Whereas transport by carriers can be either active or passive, solute flow through channel proteins is always passive.

Explanation: Channel and carrier proteins are both considered facilitated diffusion.

Diffusion and active transport involve the movement of dissolved solutes, such as sugars or mineral ions, whereas osmosis involves the transport of water only. In diffusion and osmosis, substances move down a concentration gradient. However, active transport moves substances against a concentration gradient.

Examples

• Examples of Osmosis: Examples include red blood cells swelling up when exposed to freshwater and plant root hairs taking up water.
• Examples of Diffusion: Examples of diffusion include the scent of perfume filling a whole room and the movement of small molecules across a cell membrane.

Examples of Osmosis The absorption of water from the soil is due to osmosis. The plant roots have a higher concentration than the soil, therefore, the water flows into the roots. The guard cells of the plants are also affected by osmosis.

10 Examples Of Diffusion In Everyday Life

• The smell of perfumes/Incense Sticks.
• Opening the Soda/Cold Drinks bottle and the CO2 diffuses in the air.
• Dipping the tea bags in hot water will diffuse the tea in hot water.
• Small dust particles or smoke diffuse into the air and cause air pollution.
• Breathing and taking oxygen into the body and diffuses in our blood.

Active and Passive Transport | Back to Top Passive transport requires no energy from the cell. Examples include the diffusion of oxygen and carbon dioxide, osmosis of water, and facilitated diffusion.

each group a different type of diffusion (relocation, hierarchical, contagious, or stimulus). Each group should come up with one example of diffusion for each of the four different types of scale: local, regional, and global.