Question

Which one of the following elements is necessary for the translocation of sugars in plants?
(a) Iron
(b) Manganese
(c) Molybdenum
(d) Boron

Answer 1

Hint This is the element with atomic number 5 and symbolizes B. Humans use this element as medicine for menstrual cramps, osteoarthritis, and veginal yeast infections. In plants, this element plays a very important role in cell wall formation.

Correct answer:
The element Boron is very much essential for the translocation of sugars in plants. It was discovered in the year 1910. But till now we don't have any evidence or proof which can explain the necessity of boron in the translocation of sugar. Over this, the scientist is still working to know the behavior of the boron-sugar complex inside that particular phloem cell. Scientists are also trying to find out the physical and chemical properties and also the structure of the boron-sugar complex. It was first observed in hydroponics where boron deficiency was seen and also the decreased translocation of sugar in plants was seen. Thus on the basis of the above observations, the scientists concluded that the decreased translocation of sugar in plants occurred due to the deficiency of boron.

Additional Information:
-Photosynthates are produced by the process of photosynthesis for the green plants.
- To the growing parts of the plant the sugar that is produced during photosynthesis should be delivered.
-These sugars are transported through the plant with the help of phloem cells by the process of translocation.
-The sugar was delivered to the roots shoes and developing seeds this means the growing parts of the plant.
-The sucrose is actively transported from the source cells into the companion cells and then poured into the sieve-tube elements.
-This will result in the reduction of water potential which causes water to enter from the xylem to the phloem.
-Now the resulting positive pressure forces the sugar-water mixture downwardly towards the roots where sucrose is unloaded.
-The process of transpiration causes the return of water to the leaves through the xylem vessels.

So, the correct answer is, 'Boron'.

Note:
-Earlier in 1910 it was observed that a decrease in boron decreases the translocation of sugar in plants.
-The sucrose is actively transported from the source cells into the companion cells and then poured into the sieve-tube elements.
-Source cells are the structures responsible for the production of Photosynthates.
-The sieve-tube elements are the cells in the phloem that are involved in the movement of carbohydrates.