A few drops of sap were collected by cutting across a plant stem by a suitable method. The sap was tested chemically. Which one of the following test results indicates that it is phloem sap?
Absence of sugar
Acidic
Alkaline
Low refractive index
Explanation:
Phloem sap is alkaline due to actively pumping of protons from companion cells to the outer cells.
Phloem sap is alkaline due to actively pumping of protons from companion cells to the outer cells.