Crop Phys Exam 2

Degree to which a soil can absorb and exchange cations

Carbohydrate conversion into hexose phosphates

Positive hydrostatic pressure within cells

High requirement for reducing agents to transform from sulfite to sulfide

Export of sulfur assimilated in leaves to site of protein synthesis, important antioxidant, precursor to phytochelatins-detoxification of heavy metals

Gas bubble forms in column of water and expands until column collapses

Leaf area (one side) per unit ground area

Proportionality constant that measures how easily a substance moves through a medium, function of substance type/medium/temperature

Root axial resistance, root radical resistance, stem xylem resistance, leaf xylem resistance, stomata resistance, leaf outside xylem resistance

Energy conserving phase, triose phosphate oxidation and formation of pyruvate, release of ATP and NADH

Depend on driving forces and hydraulic conductivity

C3 photosynthetic N use efficiency

Allow proteins to cross the membrane without generating ATP

Stems water composition

Mature plants sufficiently crowded to use all resources efficiently, yet not so crowded that some plants die or are unproductive, community production is optimized

Point at which the water potential of the soil is so low that plants cannot regain turgor pressure even if all water loss through transpiration ceases, water potential of the soil is less than or equal to the osmotic potential of the plant

Acts as a barrier to water and solute movement

Root water composition

Nutrients involved in redox reactions

Can theoretically be accounted for by solute and pressure potential, but can't be easily separated into these, often omitted when considering water potential

Associated with the conversion of the non-structural products of photosynthesis into new structures such as structural carbohydrates, lipids, proteins, lignins, and organic acids

Two types of tracheary elements

Nutrients that remain in ionic form

C3 typical water loss per gram of CO2 gained

Energy needed to separate molecules from liquid phase to gas

NAR*LAI

Biological process by which reduced organic compounds are mobilized and subsequently oxidized in a controlled manner

Root uptake exceeds rate of replacement of nutrient

Critical LAI in place during period of highest solar energy, maintain active leaf area over the major portion of the solar energy peak

C4 typical water loss per gram of CO2 gained

Partial oxidation of sugars to organic acids, yields small amount of energy (ATP), and reducing power (NADH)

Effective within cellular dimensions but is too slow for mass transport over long distances

Breaks down nitrite

Energy required to change temperature 1 degree C

Nutrients part of energy storage/structural integrity

Effect of dissolved solutes on water potential, reducing the free endergy of water by diluting the water

Apoplast, symplast, transmembrane

Transfer of electrons from NADH (and related species) to oxygen and synthesis of ATP

Vacuolar concentration of K

Mass flow, diffusion, crossing membranes by diffusion (across lipid bilayer or aquaporins)

Dry matter accumulation/(unit leaf area*time)

Leaf tissue water composition

Attraction of water to a solid surface

Complete oxidation of pyruvate to CO2, generates reducing power (NADH, FADH2) and 1 ATP

Band of radical cell walls in the endodermis that is impregnated with the wax-like, hydrophobic substance suberin

Nutrients part of carbon compounds

Difference in water vapor concentration between the leaf air space and the external air, the diffusion resistance of this pathway

Starter fertilizer, higher plant densities, more uniform plant spacing arrangement, weed control

Gravity causes water to move downward unless the force of gravity is opposed by an equal and opposite force

Rate of photosynthesis excluding material lost to respiration in the light. Rate observed during standard photosynthetic gas exchange measurements

Vessel elements stacked end to end form large conduits

Breaks down nitrate

Hydrostatic pressure of the solution

Maximum force per unit area that a continuous column of water can withstand before breaking

Depends on maintenance of biomass, growth, ion transport

Weak electrostatic attraction between water molecules and other molecules that contain electronegative atoms

Movement of water across a selectively permeable membrane toward the region of more negative water potential

Solute (osmotic) potential + pressure potential + gravity + matric potential

Composition of absorbed water used for growth

CAM typical water loss per gram of CO2 gained

GOGAT

Concerted movement of groups of molecules, most often in response to a pressure gradient

LAI at which canopy first reaches maximum crop growth rate

Spontaneous movement of substances from regions of higher to lower concentration

GS

Composition of absorbed water used in photosynthesis or other metabolic processes

Total amount of light energy converted into biochemical energy, Net photosynthesis + respiration in light

Dry matter accumulation/(unit ground area*time)

Water content of a soil after it has been saturated with water and excess water has been allowed to drain

C4 photosynthetic N use efficiency

Breaks down ammonium

Depends on the pressure gradient and soil hydraulic conductivity

Unit of light interception per unit LAI

Amount of biomass accumulated per solar energy received during growing season.

Area under the LAI curve

Cytosolic concentration of K

Location of the driving force for water movement through plants

Very good at high concentrations

Mutual attraction between 2 similar molecules

Measure of the average photosynthetic efficiency of leaves in a crop community, doesn't account for photosynthesis in non-leaf parts

Very good at low concentrations

Measure of the ease with which water moves through the soil, varies with soil type

Respiration associated with maintaining cellular integrity. The dominating processes are protein turnover, maintenance of ion gradients and intracellular transport processes

Composition of absorbed water transpired