5 Written Questions
5 Matching Questions
- What is water potential?
- What is cavitation?
- Transpiration is dependent upon what?
- What two driving forces drive the direction and rate of water potential gradients?
- What constitutes your stomatal complex?
- a the concentration of the solute and the pressure gradient
- b difference in water vapor concentration in the air spaces in the leaf and the external air
- c guard cells and subsidary cells found in the dumbell shaped guard cells of monocots
- d It is the formation of vapor/ gas bubble in flowing water which can rapidly collapse and produce shock waves provding energy to nucleating sites within the xylem.
- e the measurement of free energy of water per unit of volume. (J/m^3)
5 Multiple Choice Questions
- surfaces tension and adhesion at the evaporative surfaces of leaves
- via casparin cells in the endodermis, they contain radial cell walls composed of suberin (waxy substance) acting as a barrier to water making it cross the cell membrane
- gas bubbles
- the random collisions and exchange of kinetic energy between water molecules driving a movement down concentration gradients
- the formation of gas bubbles
5 True/False Questions
What 3 properties of water create __ which is important for plants? → it is the energy used to increase the surface area, the amount of surface area occupied by the interface of air and water. this is important because remember that water is more attracted to itself then to air molecules. (This is what can create contact angels) water generally wants to minimize the surface area at the air water interface
Sum up the importance of water potential: → to maintain positive tugor pressure to increase the mechanical rigidity of the cells and tissues allowing for cell growth via the stretching of cell walls
If bulk flow is driven by pressure gradient how is it responsible for movement of water through soil? → pressure is created by water via curvatures, water is going to want to move to areas of larger spaces with smaller curvatures
Water under tension such as in transport in the xylem, transmit an inward force on the cells of the xylem how is this accounted for in plant cells? → they have secondary cell walls that are very strong and lignified, they can withstand the tension
Because of rigid cell walls, change in cell water potential generally accompanied by change in hydrostatic pressure with little change in what? → changes in radius, viscosity, concentration gradient