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Quick Quick Need Help Osmosis

  1. Mar 21, 2005 #1
    Quick Quick Need Help Osmosis!!

    Hi i need help answering these questions....

    You can restore wilted flowers or vegetables by soaking them in water. From your knowledge of osmosis, would it be better to saok them in distilled or tap water?

    Explain why it is important for intravenous fluids to be of the same solute concentration as human blood

    Road salt taht has been accidentally spilled on grass often kills the grass. Explain why this happens

    Please If u know one of the questions very well... Please, try your best in answering the question better.
  2. jcsd
  3. Mar 21, 2005 #2


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    I will answer the question for you but I will point you on the right track. If you know the key element of osmosis you should be able to answer the question.

    What is the difference between distilled and tap water? What are removing from the tap water when you distille the tap water?

    What happens to cells such as red blood cell that at a physiological solute concentratrion and are then expose to solution that are either over or under the physiological solute concentration.

    What happen to 2 solution at different salt concentration that are seperated by a semi-permiable membrane (i.e. it only lets water get out). How does it related to cells?
  4. Mar 21, 2005 #3
    I guess you know the basic idea of osmosis: water moves in or out of the cell based on where the concentration of disolved substances is highest, if there is a higher concentration outside the cell water will move out and if there is a higher concentration inside the cell water will move in, if there is the same concentration inside and outside the cell no water will move in or out.

    You can answer all your questions with this knowledge, just think about the direction in which water will go in each case.
  5. Mar 21, 2005 #4
    Distilled water is better because it is pure water and does not have the unnecessary minerals like tap water. Distilled water will have the tendency to have a lower concentration than the flower. This will increase the amount of water the flower will absorb through osmosis. Therefore Osmosis will occur faster for distilled water because the low concentration of the distilled water will move into the plant.
    The reason why Isotonic is the appropriate choice is because the intravenous fluid has the same osmotic pressure as the human blood. It cannot be hypertonic because the intravenous fluid has more solute, which would mean the movement of the human blood will be towards the hypertonic solution, this would be harmful to the human. Hypotonic solution will not work as well because there would be less solute, so the movement of blood is away from the hypotonic solution. Hypotonic solutions will have a lower number of particles than the blood, Hypertonic solutions have a higher number of particles than the blood, and Isotonic fluids will have the same number as particles as the blood, this will result in a fast fluid balance. Plus when a low solute concentration moves into a high solute concentration, its job is to create equilibrium.

    these are my answers can you guys check them... plus i havent yet gotten the last one.... i will try though.
  6. Mar 21, 2005 #5


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    The blood isn't moving towards and away from these solutions.
    Think about what would physically happen to the cells in the blood and the rest of your body, if the solution surrounding them became hypotonic (less concentrated with ions) or hypertonic (over concentrated with ions). Suppose you were dehydrated, how would you replenish the fluid in your cells? :rolleyes:
  7. Mar 21, 2005 #6
    Hypertonic--The Cell shrivels
    Hypotonic-- The Cell bursts

    Am i correct
  8. Mar 21, 2005 #7
    I am sorry, I do not understand The salt problem with the grass, sorrry. Can someone elaborate on this more?
  9. Mar 21, 2005 #8


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    You are right !! :biggrin:
  10. Mar 21, 2005 #9
    WOW I JUST GOT THE ANSWER, JUST POPPED IN MY HEAD!!! please tell me if im rght!!!

    Osmosis also helps destroy and kill grass. Grass just like plants need to take in CO2 and water during photosynthesis. The reason why salt kills grass is because, the grass needs water to be allowed to enter and leave. If the grass’ soil is to salty, than hypertonicity occurs, and the cells will kill the roots of the grass. When the roots have been killed the grass die along with it. So in conclusion grass will shrivel up and die in a soil that is to salty.
  11. Mar 21, 2005 #10


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    You are definately on the right track. :smile: But how did the cells of the roots die?

    You've told us where the higher concentration of ions is.. You still are deailing with a fluid (I'll let you figure out where the fluid is. :uhh: Hint: it's not in the road salt). So what physically happens to the grass cells? :rolleyes:
  12. Mar 21, 2005 #11
    The cells of the roots die because they are not available to the water, so they suffocate.
  13. Mar 21, 2005 #12

    The water surrounding the roots has a high concentration of disolved salt, so water will be drawn out of the cells of the grass' roots, as you said yourself:

  14. Mar 21, 2005 #13
    lol sorry thats what i meant to say
  15. Mar 22, 2005 #14
    thanks everyone for helping, i appreciate it!
  16. Mar 22, 2005 #15


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    You gave Karma a lot of latitude on that one gerben :biggrin:
    Wasn't she/he referring to intravenous fluid and blood cells in her quote?
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