Chapter 23, Problem 13WIO

Summary Introduction

To determine:

The tissue in which it is expected to find the radioactive material immediately after exposure to the labeled carbon and during transport if a scientist has exposed a leaf to ${\text{CO}}_{\text{2}}$ labeled with radioactive carbon-14. Also determine whether the radioactive material will be above, below the leaf of a plant or both when transport is completed.

Concept introduction:

Phloem sap is the organic compound consisting sugars, amino acids, hormones, enzymes water and minerals. The sugar is mostly dissolved carbohydrates like sucrose. It is synthesized at source part of the plant. The source parts of the plant are capable of synthesizing sugars in the presence of sunlight by the process of photosynthesis. The photosynthetic cells present in leaves are capable of photosynthesis. Thus, phloem cells originate in the photosynthetic cells only.