Question

The water potential of pure water is
A)More than one.
B)Zero.
C)Less than zero.
D)More than zero but less than one.

Answer 1

Hint: A number of different possible water flow motors, which may work in the same or different directions, are incorporated into the water potential. There may be several possible influences functioning concurrently within complex biological processes. The addition of solutes, for example, decreases the potential (negative vector), while an increase in pressure raises the potential for solutes (positive vector).

Complete answer:
In reference conditions, water potential is the potential energy of water per unit volume compared to pure water. Due to osmosis, gravity, mechanical strain and matrix effects, such as capillary action, water potential quantifies the ability of water to pass from one place to another (which is caused by surface tension). In understanding and computing the flow of water within plants, animals, and soil, the principle of water capacity has proven useful.

Usually, water potential is expressed in potential energy per unit volume and is represented most much by the Greek letter ψ.
Water potential is the measurement of usable energy in water. Water's potential depends on the concentration of water solutions. As no solute molecules are present in pure water, the need for water is negligible. The incorporation of solute decreases liquid potential. If a solution is enclosed by a solid cell wall, the flow of water through the cell can exert pressure on the cell wall.

Hence, the correct answer is option (B)

Note: Water with dissolved salt, like sea water or the fluid in a living cell, is a typical example. These solutions, compared to the pure water relation, have negative water capacity. With no flow constraint, water can travel from the higher potential locus (pure water) to the lower potential locus (solution); flow continues until some water potential element, such as pressure or elevation, is equalized or balanced by the difference in potential.