Question

Identify the correct statements related to the uptake of mineral ions

A. The membrane proteins pump ions from soil into the cytoplasm of epidermal cells

B. Transport proteins of endodermal cells act as control points, which adjust the quantity and type of solutes reaching the xylem

C. Root endoderm due to its suberin layer, can not transport ions

• A. A & B
• B. B & C
• C. A & C
• D. A, B & C

Answer 1

The correct option is A

A & B

Root endodermis, because of the layer of suberin is impermeable to ions passively. Therefore, ions are actively transported into the root epidermal cells by different membrane pumps, but once taken in, the ions are trapped and cannot leave the cells, thus ensuring that the ions are transported unidirectionally.