Final answer:
The two main bulk flow processes in plants are translocation and transpiration. Translocation is the transport of organic compounds through the phloem from source to sink, while transpiration is the loss of water from the leaves that creates a negative pressure gradient for water movement.
Step-by-step explanation:
The two main bulk flow processes in plants are translocation and transpiration.
Translocation is the process of transporting organic compounds, such as sugars, from the source (e.g., leaves) to the sink (e.g., roots or developing fruits) through the phloem. This process relies on pressure differences created by the addition and removal of solutes in different regions of the plant.
Transpiration is the loss of water from the leaves through small openings called stomata. This loss creates a negative pressure gradient that pulls water up through the xylem from the roots to the leaves, allowing for the movement of water and dissolved nutrients in the plant.