Water Potential Vocabulary Flashcards

A set of vocabulary flashcards covering key terms, symbols, formulas, and units related to water potential from the lecture transcript.

Water Potential

The potential energy of water per unit area compared to pure water, allowing one to determine the direction of water flow due to osmosis, gravity, pressure, and surface tension.

Psi ($\psi$)

The symbol used to represent water potential, which resembles the trident carried by Poseidon, the Greek god of the ocean.

Solute Potential ($\psi_S$)

The component of water potential that decreases as the concentration of solutes in a solution increases, driven by osmosis.

Pressure Potential ($\psi_P$)

The component of water potential resulting from physical pressure exerted on or by a cell, such as the inward pressure exerted by a cell wall.

Water Potential Equation

The formula used to calculate total water potential: $\psi = \psi_P + \psi_S$.

Water Potential of Pure Water

The baseline water potential measurement for pure water, which is equal to $0\,bars$.

Direction of Water Movement

The natural flow of water across a membrane, moving from an area of high water potential to an area of low water potential.

Solute Potential Equation

The formula used to calculate solute potential: (\psi_S = -iCRT).

Ionization Constant ($i$)

A unitless factor in the solute potential equation ranging from $1$ to $2$, representing the number of particles a molecule forms when dissolved in water (e.g., $2$ for sodium chloride and $1$ for sucrose).

Molar Concentration ($C$)

The concentration of a solute in a solution, measured in moles per liter (molarity).

Pressure Constant ($R$)

A fixed constant value used in the solute potential formula equal to $0.0831\,liter\,bars/mole\,K$.

Temperature ($T$) in Solute Potential

The absolute temperature value measured in Kelvin ($K$), calculated by adding $273$ to the temperature in degrees Celsius ($^\circ\text{C}$).

Open Beaker Pressure Potential

The physical pressure potential of a solution in an open container, which has a value of $0\,bars$.