Which one of the following statements about phloem is correct?

Phloem is a specialized vascular tissue in plants primarily responsible for the translocation of photosynthetic products, such as sucrose and other soluble sugars, from the leaves (sources) to various parts of the plant like roots, fruits, and seeds (sinks) [3]. While xylem is responsible for the transport of water and minerals from the soil [3], phloem facilitates the movement of food, amino acids, and signaling molecules in both upward and downward directions [2]. Structurally, phloem is classified as a complex permanent tissue because it consists of multiple cell types, including sieve tube elements, companion cells, phloem parenchyma, and phloem fibers [2]. Unlike xylem, which provides significant structural support through lignified vessels, phloem's primary role is nutrient distribution rather than mechanical support. This transport process, known as translocation, is driven by osmotic pressure and requires energy in the form of ATP [2].

Sources

1. [2] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > Transport of food and other substances > p. 95
2. [3] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > 5.4.2 Transportation in Plants > p. 94
3. [1] Science , class X (NCERT 2025 ed.) > Chapter 5: Life Processes > Transport of food and other substances > p. 96