Question

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 pholem sap?

• A. Low refractive index
• B. Absence of sugar
• C. Acidic
• D. Alkaline

Answer 1

The correct option is D Alkaline

Phloem sap is generally alkaline with pH ranging from 7.3 - 8.5 and contains high levels of K${}^{+}$ and Mg${}^{2+}$. Hence, the chemical test for alkalinity will help to identify that the exudated sap is phloem sap.

So, the correct answer is 'Alkaline'.