Translocation of Substances in the Phloem

Photosynthesis takes place in the mesophyll cells and, in C4 plants, in the bundle sheath cells of the leaf (see Figure 8.16). The products of photosynthesis (primarily carbohydrates) diffuse to the nearest small vein, where they are actively transported into sieve tube elements.

Substances in the phloem move from sources to sinks. A source is an organ (such as a mature leaf or a storage root) that produces (by photosynthesis or by digestion of stored reserves) more sugars than it requires. A sink is an organ (such as a root, a flower, a developing fruit or tuber, or an immature leaf) that consumes sugars for its own growth and storage needs. Sugars (primarily sucrose), amino acids, some

Question: Are organic solutes translocated in the xylem or in the phloem?

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Good Carb Diet

Good Carb Diet

WHAT IT IS A three-phase plan that has been likened to the low-carbohydrate Atkins program because during the first two weeks, South Beach eliminates most carbs, including bread, pasta, potatoes, fruit and most dairy products. In PHASE 2, healthy carbs, including most fruits, whole grains and dairy products are gradually reintroduced, but processed carbs such as bagels, cookies, cornflakes, regular pasta and rice cakes remain on the list of foods to avoid or eat rarely.

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