5 Written questions
5 Matching questions
- What is the pit membrane of the xylem and why is it important to water transfer?
- What properties of water generates the physical forces to pull water up through the plant?
- Why doesn't water boil under the tension created during transport in the xylem?
- Fisk's first law:
- a diffusion rate is directly proportional to the concentration gradient
- b surfaces tension and adhesion at the evaporative surfaces of leaves
- c this is a porous layer between the 2 pit pairs, made of 2 primary walls and a middle lamella. This membrane helps to prevent the spreading of gas bubbles within the xylem
- d the cohesion and adhesion properties of water make the liquid to vapor activation high in water, within the xylem the energy is not available to under go the change
- e transfer of water traveling between cell walls and any extra cellular spaces that have water in it on it's way to the root cortex driven by hydrostatic pressure
5 Multiple choice questions
- tensile strength. this is the maximum force per area that a continuous column of water can stand before breaking
- There are no metabolic pumps to drive water, it only occurs when water is coupled with ion (solutes) to carry it. This can occur because the loss of the free energy by the solute is greater then the gain of free E of the water. (negative net change in E is produced)
- a layer on the outside of the epidermis that is not water permeable
- cellulose and microfibril
- apoplast, symplast and transmembrane
5 True/False questions
What two things is the rate of water flow to a plant dependent upon? → the absolute concentration difference (moles/cubic meters) this is effected by temperatures
What two driving forces drive the direction and rate of water potential gradients? → solute concentration, pressure and gravity
In most plants as turgor pressure approaches zero what happens to the relative cell volume? → there is a negative hydrostatic pressure
What is solute potential and what does it do? → the measurement of free energy of water per unit of volume. (J/m^3)
What main things effect water potential? → type of median, the begging state of the cell (flaccid or turgid), and the pressure