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Biology Paper 1

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cox mesophyll is covered with water film and it leaves there when they r heated into the air spaces as a result more water potential inside the plant and water vapours move out by difussion though stomata

yes, but main cause is stomatal openings,
 
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stomal opening causes water to move out by diffusion! they said where MOST evapouration occured. i guess they did not highlighted stoma but they highlighted guard cell but most evapouration occurs from spongy cells while stoma is not responsible for evapouration. its only role is closing and opening plus what if they said where most CO2 dissolves for at daytime? would u say stoma or film covering mesophyl?

1) i think they pointed the spaces between guard cells (stomata)
2) evaporation was not mentioned, water loss from the leaf was mentioned
3) CO2 enters through stomata
 
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1) if even stoma wa mention it seemed wrong to me
2) i remember the question well cox i thought a lot over it it said " Where does Most Evapouration occured in a leaf" the keywords i remember were most and evapouration rest of the question idk
3) CO2 enter though stoma but doess not dissolve over there it dissolves in water and then moves in the cell

that was a similar question to others which came in past papers, i think they just changed the wordings, like they did with lactose one, that mcq was same but wording was different
 
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1) if even stoma wa mention it seemed wrong to me
2) i remember the question well cox i thought a lot over it it said " Where does Most Evapouration occured in a leaf" the keywords i remember were most and evapouration rest of the question idk
3) CO2 enter though stoma but doess not dissolve over there it dissolves in water and then moves in the cell

just check D2000 p1 q14
 
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ahan last year question they said where does water leaves the leaf this time it was evapouration. thats the point they want to assess students kay past ppr kay rattay lagaiyn haan ya unko samjha bhi ha!

no, the one i quoted mentions water loss (evaporation)
 
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http://coachsci.sdsu.edu/csa/vol36/rushall1.htm
During exercise the body produces a great deal of heat. In extreme circumstances this can elevate its core temperature from 37° C to beyond 40° C. When the surrounding air is cool heat can be lost from the body by the process of radiation (transfer of heat by electromagnetic waves), convection (by air movement), conduction (by contact), and evaporation (by sweating). As the surrounding temperature increases it becomes more and more difficult to lose heat by radiation, convection, and conduction. Hence, the predominant source of heat loss in warm to hot conditions is from the evaporation of sweat on the skin surface.

According to this the answer of question 20 homeostasis should have been D. What are everyone's thoughts?
 
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