#Question id: 11800
#SCPH05 I Biotechnology
There are at least three different types of companion cells
in the minor veins of mature, exporting leaves. Which of the following
statements about these companion cells is CORRECT?
a.) transfer cells are transport sugars enter the apoplast
during the movement of sugars from mesophyll cells to sieve elements. Transfer
cells transport sugars from the apoplast to the symplast of the sieve elements
and companion cells in the source.
b.) the numerous mitochondria in companion cells may supply
energy as ATP to the sieve elements
c.) Ordinary companion cells can function in either
symplastic or apoplastic short-distance transport in source leaves, depending
in part on plasmodesmatal frequencies
d.) Intermediary cells, by contrast, function in symplastic
transport of sugars from mesophyll cells to sieve elements