Water Potential and Absorption in Plants

Front

What is water potential and how is it represented?

Back

Water potential is a measure of water’s potential to do work, represented by the Greek letter Psi (Ψ) and measured in bars, pascals, or atmospheres.

Front

How does water move in relation to water potential?

Back

Water always moves from an area of high water potential to an area of low water potential.

Front

What is the water potential of pure water at normal temperature and pressure?

Back

The water potential of pure water at normal temperature and pressure is zero.

Front

What are the components of water potential?

Back

The components of water potential are matrix potential (Ψm), solute potential (Ψs), and pressure potential (Ψp).

Front

What is the equation for water potential in plant cells?

Back

The equation for water potential in plant cells is Ψw = Ψs + Ψp.

Front

What is solute potential (Ψs)?

Back

Solute potential (Ψs) is the amount by which the water potential is reduced due to the presence of solute, expressed in negative values.

Front

What is pressure potential (Ψp)?

Back

Pressure potential (Ψp) is the pressure exerted by the plant cell wall on the cellular contents, usually positive and related to turgor pressure.

Front

What is the significance of root pressure in plants?

Back

Root pressure helps push water and nutrients up from the roots to the rest of the plant, especially when transpiration is low.

Front

What is the process of active absorption of water?

Back

Active absorption involves root cells actively taking in water, using metabolic energy, and can be osmotic or non-osmotic.

Front

What is the difference between osmotic and non-osmotic absorption?

Back

Osmotic absorption occurs when water is absorbed according to the osmotic gradient, while non-osmotic absorption occurs against the osmotic gradient.