Sap is the nutrient rich liquid that circulates within a network of vessels that run throughout a plant. Raw sap is composed of water and the minerals absorbed by the roots from the soil. A conductive tissue called xylem transports the raw sap to the leaves. Through a process called photosynthesis, the leaves manufacture sugar molecules from the components of raw sap and carbon dioxide from the atmosphere. Elaborated sap is the result of photosynthesis which is then distributed to the plant's other leaves and stems by the phloem, the conductive tissue running parallel to the xylem. Autotrophic plants absorb nutrients and transform them into living matter through photosynthesis. Heterotrophic plants depend on other organism to feed themselves like mistletoe which pumps raw sap from the host plant and then transforms it by photosynthesis to nourish itself.

Originally released by QA International, 2006. Streaming video file encoded with permission for digital streaming by Infobase on May 06, 2015.

Sap (1:00); .