The translocation of organic solutes in sieve-tube members is supported by:
Correct answer: D. Mass flow involving a carrier and ATP
- A. Cytoplasmic streaming
- B. Root pressure and transpiration pull
- C. P-proteins
- D. Mass flow involving a carrier and ATP
Explanation
According to the mass flow hypothesis, the transport of organic solutes takes place from source to sink, this transport also depends on metabolic energy. According to the cytoplasmic streaming hypothesis (which was given by de Vries, in 1885) the transport of organic solutes takes place by a combination of diffusion and cytoplasmic streaming. Cytoplasmic streaming carries organic solutes from one end to the other end of the sieve tube. P-proteins have a role as a defense against phloem-feeding insects and the sealing of damaged sieve tubes. So, the correct answer is 'Mass flow involving a carrier and ATP'. So correct option is C.
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