Which tissue in vascular plants transports sugars and nutrients?

Which tissue in vascular plants transports sugars and nutrients?

• A. Xylem
• B. Root hairs
• C. Phloem
• D. Cortex

Answer: (C)

Phloem is the tissue that transports sugars and nutrients through vascular plants. It carries the organic products of photosynthesis, mainly sugars like sucrose, from where they are produced (the leaves and other photosynthetic tissues) to parts of the plant that need them (growing shoots, roots, fruits, and developing seeds). This movement, called translocation, uses living cells arranged in sieve tubes with help from companion cells, and it can go in multiple directions depending on where the sugars are produced and required. The mechanism is often described as the pressure-flow model, where loading sugar into the phloem lowers the water potential, water enters by osmosis, generating pressure that pushes the sap along to sink tissues. In contrast, xylem mainly transports water and minerals from roots upward to the shoots and leaves, driven largely by transpiration. Root hairs are tiny extensions of epidermal cells that increase surface area for water uptake from the soil, not long-distance nutrient transport, and the cortex is the ground-tissue layer inside the root or stem that stores substances and supports the vascular system rather than serving as the primary transport pathway for sugars.

Phloem is the tissue that transports sugars and nutrients through vascular plants. It carries the organic products of photosynthesis, mainly sugars like sucrose, from where they are produced (the leaves and other photosynthetic tissues) to parts of the plant that need them (growing shoots, roots, fruits, and developing seeds). This movement, called translocation, uses living cells arranged in sieve tubes with help from companion cells, and it can go in multiple directions depending on where the sugars are produced and required. The mechanism is often described as the pressure-flow model, where loading sugar into the phloem lowers the water potential, water enters by osmosis, generating pressure that pushes the sap along to sink tissues. In contrast, xylem mainly transports water and minerals from roots upward to the shoots and leaves, driven largely by transpiration. Root hairs are tiny extensions of epidermal cells that increase surface area for water uptake from the soil, not long-distance nutrient transport, and the cortex is the ground-tissue layer inside the root or stem that stores substances and supports the vascular system rather than serving as the primary transport pathway for sugars.