20. About the nutrient translocation (source-sink) during photosynthesis, which one of the following is thebest answer?
(A)Mesophyll cells can transport the sugar into phloem by passive transport.
(B) Junior leaf is considered as a source tissue.
(C) Companion cell can provide ATP to facilitate the phloem sugars transport into sink tissue.
(D)The concentration of sugar in photosynthetic mesophyll cells is lower than phloem.
(E)The concentration of sugar in the apical meristem is higher than phloem.