What is the primary function of phloem in vascular plants?

The primary function of phloem in vascular plants is to transport organic nutrients, primarily sugars, throughout the plant. This process is essential for the plant’s growth and development because it allows for the distribution of the energy-rich compounds produced during photosynthesis from the leaves, where they are synthesized, to other parts of the plant, including roots, stems, and developing fruits and seeds.

Phloem consists of specialized cells that enable this transport, primarily through a phenomenon known as translocation. The sugars, particularly sucrose, dissolve in water to form a sap that flows through the phloem vessels, ensuring that all parts of the plant receive the necessary nutrients to thrive. The effectiveness of this system supports not only the growth of the plant but also its ability to adapt to varying environmental conditions.

Understanding this function is critical for areas such as agriculture and horticulture, where nutrient transport can significantly affect crop yields and plant health. The other options all pertain to different plant functions—water transport is the role of xylem, nutrient storage usually happens in specialized tissues, and structural support is also provided by xylem and other plant structures.