Guard cell hyper or hypo?

[hunterpostbacst]

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During the day, guard cells fill with glucose, becoming more concentrated than their environment and water flows in(turgid). The cell can be said 'hypertonic'? relative to their environment?

 

[nze82]

During the day, guard cells fill with glucose, becoming more concentrated than their environment and water flows in(turgid). The cell can be said 'hypertonic'? relative to their environment?

Yes! Due to higher concentration of solute, guard cells are considered to be hypertonic with respect to their surrounding environment.

 

[TerpDentist]

I thought that when water flows into the cell because the inside has a higher solute concentration, that is hypotonic. I'm basing this on the Kaplan white book that uses the way to remember this being hyp-O-tonic, by thinking of the O as a cell that has swollen up.

Am I completely wrong on this?

 

[bigstix808]

During the day, guard cells fill with glucose, becoming more concentrated than their environment and water flows in(turgid). The cell can be said 'hypertonic'? relative to their environment?

yes, the inside is hypertonic to the surrounding environment but glucose is not the main key player in this...K+ is. it is activley pumped in from adjacent cells which causes a change in tonicity in which water passivly follows making the cells turgid and the stomata open up

 

[GiTsticker]

Am I completely wrong on this?

Yes. 😛 If water can flow from hypotonic solution to hypertonic solution, it will until the two solutions are isotonic. (Or until the osmotic pressure comes to equilibrium with any other opposing forces present.) However, if you have two cells with equal solute concentrations, and you pump a lot of water into one of them, then that one will become hypotonic compared to the other cell.

 

[Dental Jarry]

When kaplan says hyp O tonic makes the cells swell, they are referring to the outside environment. If the outside of the cell is hypotonic than the cell will swell with water. That, however would make the inside of the cell hypertonic.