Xylem//Phloem (1 Viewer)

[kimmeh]

One of the MCQ questions in CSSA 2001:

identify the correct statement about the moevment of materials in the xylem

a)organic compounds are transported in the xylem
b) transport of materials in the xylem is both up anmd dodnw
c) inorganic compounds and waste are transported in the xylem
d) inorganic and organic compounds are transported in the xylem


The answer says C, but CSSA have been known to produce wrong answers in their MCQ. What are your opinions? i thought it was none of them since the xylem only transports water and minerals UP..

 

[babydoll_]

C sounds the closest. Xylem transports water and minerals UP the plant

 

[Calculon]

Is not B cos it only goes up
Its not A because water isnt an organic compound
Its C or D but I dont know which

 

[queenie]

C.
a)organic compounds are transported in the xylem
b) transport of materials in the xylem is both up anmd dodnw
c) inorganic compounds and waste are transported in the xylem
d) inorganic and organic compounds are transported in the xylem

The xylem transports water and some mineral ions and it only travels one way (up). So its not b.

Minerals are naturally occuring INORGANIC substances. so its not a OR d.
:. the xylem only transports inorganic substances, and so the answer is C (by elimination)

 

[04er]

i would have thought D, but only because the 'waste' part in C got me confused.

 

[queenie]

Originally posted by 04er
i would have thought D, but only because the 'waste' part in C got me confused.

xlyem doesnt trasport organic substances though.. thats the phloem's job.

 

[xiao1985]

yea... i would think c is the closest... aprt from the waste bit is uhm... abiguous... a, b and d (edited) are definitely wrong...

 

[queenie]

yea, the waste thing does throw me off to.. but the only products plant need in order to carry out photosynthesis is water and carbon dioxide.. wouldnt everything else be considered a waste as its not needed by the plant?

 

[xiao1985]

perhaps roots does not have teh aiblity to exclude/excrete waste... hence dissovled waste has to be transported along with water... but that would be out of hsc scope...

as far the hsc is concerned, i think, a b d are wrong, hence leaving c the correct answer...