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Friday, 5 April 2013

How do substances like CO2 and water move in and out of the cell?

1. How do substances like CO2 and water move in and out of the cell? Discuss.
Answer: 
Gases like carbon dioxide and oxygen move in and out of a cell by diffusion from the region of high concentration to low concentration.

15 comments:

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  2. Carbon dioxide is a small nonpolar molecule which means that it can easily diffuse through the lipid bilayer of the cell membrane. Carbon dioxide moves from an area of high concentration to an area of low concentration. Diffusion is passive transport (no ATP required).

    Water is a polar molecule but it is pretty small so it can still dissolve through the lipid bilayer into the cell. The movement of water from an area of lower solute concentration to an area of higher solute concentration across a semi-permeable membrane is called osmosis. Aquaporins are small water channels embedded in the lipid bilayer. These protein water channels provide a hydrophilic (polar) tunnel through the lipid bilayer for the fast movement of water across the membrane.. Aquaporins are a form of facilitated diffusion (diffusion with "help"). Osmosis and facilitated diffusion are forms of passive transport.

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  5. The answer is to up to the point. It must be edited or replaced by a better answer.....

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  6. Gases like Co2 and O2 move In and Out of the cell by the process of diffusion from their region of high solute concentration to region of low solute concentration.

    Water passes through cell membrane both inwardly as well as outwardly. Net movement of water occurs according to the solute concentration through semipermeable membrane. This process is called Osmosis. If the cell is place in Hypertonic solution, water comes out of the cell and exosmosis takes place. But if the cell is placed in Hypotonic Solution water moves inside the cell from external environment and endosmosis takes place.

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    1. Nice explaination
      👊👊👊😀

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  7. Substances like CO2 move in and out of the cell by the process of diffusion. When the concentration of CO2 accumulates in the cell and is higher than the cell's external environment, it moves out and is thus excreted. Similarly, when its concentration is lower in the cell as compared to outside the cell, it moves into the cell.
    Water also moves in and out of the cell by the same principle of difference of concentration, but the process through which water moves across a selectively permeable membrane is called osmosis.

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