HORTICULTURE

HORTICULTURE SCIENCE

PLANT BIOLOGY

Question [CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
What causes the movement of water through the xylem?
A
gravity
B
active translocation
C
active transport in root tissue
D
evaporation of water from leaves
Explanation: 

Detailed explanation-1: -Transpiration is ultimately the main driver of water movement in xylem. The cohesion-tension model works like this: Transpiration (evaporation) occurs because stomata are open to allow gas exchange for photosynthesis.

Detailed explanation-2: -The cohesion – tension theory of sap ascent explains how how water is pulled up from the roots to the top of the plant. Evaporation from mesophyll cells in the leaves produces a negative water potential gradient that causes water and minerals to move upwards from the roots through the xylem.

Detailed explanation-3: -1-Water is passively transported into the roots and then into the xylem. 2-The forces of cohesion and adhesion cause the water molecules to form a column in the xylem. 3-Water moves from the xylem into the mesophyll cells, evaporates from their surfaces and leaves the plant by diffusion through the stomata.

Detailed explanation-4: -Osmosis plays a central role in the movement of water between cells and various compartments within plants. In the absence of transpiration, osmotic forces dominate the movement of water into roots.

Detailed explanation-5: -Transpiration is the process of water movement through a plant and its evaporation from aerial parts, such as leaves, stems and flowers.

There is 1 question to complete.