Question

Assertion translocation of solutes take place across phloem
reason solutes can be translocated both in upward direction​

Answer 1

Answer:

Phloem transport is the long distance movement of organic substances from the source or supply end (region of manufacture or storage) to the region of utilisation or sink. But the source and sink may be reversed depending on the season or need of the plants. Sugar stored in roots may be mobilized to become a source of food in the early spring when the buds of trees act as sink and require energy for their growth and development. Since the source- sink relationship is variable, the direction of movement of organic solutes in phloem can be upwards or downwards i.e., bidirectional.

So, the correct answer is 'Both Assertion and Reason are correct and Reason is the correct explanation for Assertion'.

Explanation:

Answer 2

Assertion translocation of solutes takes place across phloem.

Reason solutes can be translocated both in an upward direction​.

In this both Assertion and Reason are correct.

• Sources are photosynthesis structures that create photosynthates for the developing plant. Sugars generated in sources like as leaves should be translocated to the plant's growth portions via the phloem. Sinks are the locations where sugar is delivered, such as roots, new shoots, as well as developing seeds. Depending on the stage of growth of the plant and the season, seed, tubers, or bulbs can act as a source or even a sink.
• The phloem is normally used to transport the product from origin to the nearby sink.
• Upward translocation occurs mostly during seed, tuber, and other plant germination. When food is placed & transformed into a soluble form, it is supplied to the immature seedling's upper growing portion it until produces green leaves.
• Upward translocation of solute molecules occurs through the stem to immature leaves, buds, & flowers located at the branch's tip.