Card Set Information

2012-02-14 01:43:58
plant growth week notes

plant growth week 1 notes
Show Answers:

  1. What are some major properties of water? and explain
    • High specific heat- takes a lot of E to heat up water and its buffers temp changes well
    • high heat of vaporization- good for evaporation
    • cohesion- water likes to stick to water
    • adhesion- water likes to stick to other surfaces
    • capillarity- water has abililty to climb
  2. what are three ways water moves things? explain
    • Bulk Flow- many types of mol. moving together
    • Diffusion- mol.moving from high Concentration to low
    • Osmosis- water mol. diffuse through selective membrane
  3. explain water potential and its three components
    water potential is the free E of water. the ability of water to do something. 3 components- Solute potential, pressure potential and gravity potential
  4. explain water potential of flacid cell dropped into a sucrose solution after it reaches equilibrium
    water flows into cell so there is and increase in pressure potential of cell, and the water potential is then increase.
  5. what is the primary force that drives water from soil to air?
  6. what three ways is water taken up into the system? explain them
    • Apoplast pathway- goes in between cells
    • Symplast- goes through cells
    • Casparian strip- allows apoplast to transport into symplastic pathway to get to xylem
  7. Most water moves across membranes through _________
  8. what are 2 forces that dive water uptake into roots?
    High solute concentration and transpiration
  9. Stomata are controlled by what type of cells?
    guard cells
  10. water transport is done mainly through _______
  11. Transport occurs through ______ driven__________
    pressure , bulk flow
  12. when you have low water potential and low pressure potential in th leaves what happen?
  13. what is the purpose of the pits in the vessels or tracheids?
    pits stop bubbles from becoming too great and causing embolesm
  14. what are the essential elements required for plant growth and where are they obtained. Where are other essential nutrients absorbed in the plant
    C O H from the air and Rhizosphere absorbs other essential nutrients
  15. How do the minerals enter the apoplast?
    Bulk flow by diffusion
  16. what are the three ways that minerals can go through membrane?
    • 1. when it first goes into symplast
    • 2. Symplast to xylem
    • 3. in and out of vacuoule
  17. what is the difference between channels carriers and pumsp?
    channels are non specific and gates and work through diffusion, carriers are slower bc they are specifi and use passive transport to facilitate diffusion or secondary active transport to counter diffusion. pumps use E from ATP to counter diffusion
  18. what are two ways plants scavenge nutrients in poor soils?
    carniverous and mychorizal fungi
  19. Minerals enter the ______ by _______ together with wwater by ________
    apoplast, bulkflow, diffusion
  20. Minerals move to the shoot and the leave in the _______
    transpiration stream
  21. What are the three ways nutirnets get into the membrane?
    • 1. when they first go into the symplast
    • 2. from the symplast to the xylem
    • 3. in and out of vacuoules
  22. What are different types of active transport and describe them
    primary and secondary. Primary uses pumps to move solutes againts their conc. gradient. secondary moves solutes against each other one with gradient one against.
  23. define ectotrophic and arbuscular
    dense mantel of mucellium and penetrate root cells and create arbuscles
  24. Plants control the distribution of solutes in the plants by controlling solutes movement across membranes where do plants exert control over mineral uptake?
    carrier, transport proteins, pumps. they occur in cell membrane.
  25. a carrier has passive, secondary or primary active transport?
    passive by facilitating diffusion and secondary active with use of symporter/antiporter
  26. channels use what kind of transport. primary active secondary active or passive
    use passive
  27. what is the "endosymbiotic theory"
    that chloroplast resemble engulfed cyanobacteria
  28. which structures in the chloroplast resemble cytoplasm
    stroma and luemen
  29. light is both a ______ and a _______
    wave, particle
  30. explain "rain of photons"
    E and info
  31. light is absorbed by what pigments
    chrlorphyll a and b. caretonoids beta-carotene, lyopene, and leutein
  32. what is the diff. between the light and dark rxns?
    • Light- E from sun converted to chem. E
    • dark- chem E is used to fix C
  33. Decribe the light harvesting complex and how it works.
    light hits the pigment mol during the E tranfer phase then is tranfered to a reaction center during the electron transfer phase and the electrons work with the rxn center either as electron donors or acceptors
  34. describe the ETC
    light rxns organ. on thylakoid membrane. water gets oxidized in lumen by chlorophyll in photosystem 2 rxn center leaving protons in lumen. Electrons are excited to high E state and passed to platoquinones whihc bind H from stroma. then reduced plastoquinones tranfer electrons to cytochrom b64. then passed to plastocyanin then transfers electrons to photosystem 1 then passed to ferrodoxin and reduces NADP to NADPH
  35. explain the ATP synthesis process
    protons in lumen form electochem. gradient across thylakoid membrane ATP synthase couples proton movement to ATP synthesis through photophosphorylation
  36. The Calvin cycle uses____ and _____ to convert _____ to sugar
    NADPH, ATP, carbon dioxide
  37. explain the products of regeneration and carboxylation. and the products after regeneration
    3 ribulose bisphophates + 3 carbon dioxides ----> 6 triose phosphates. 3 ribulouse bisphosphate+ 1 net triose phosphate
  38. Describe RuBisCO activation
    ATP from light activates RuBisCO activase and RuBisCO leads to carboxylation. The light E also decrease the protons in the stroma causeing modulation of RuBisCO which adds a C to and causes carboxylation
  39. ______ can also oxygenate ribulose bisphosphate triggereing photorespiration.
  40. what is the end product of the photorespirtation
    3 triose phosphates and 1 carbon dioxide
  41. T/FWhen CO2 is limiting excess reducations acculate and it can be damaging to ETC
  42. ________ consumes excess reductants when CO2 is limiting and reduces damage to photosystems
  43. ______ and _______ are affected by CO2 concentration and temp.
    carboxylation and oxygenation
  44. What happens in photorespiration when there are high temps
    increases RuBisCO oxygenationand reduce uptake of CO2 from air
  45. ________ evolved in hot climate plants to increase CO2 concentrations around RuBisCO
    C4 photosynthesis
  46. How is carbon initially fixed in the C4 photosynthesis
    PEP carboxylase converts PEP to oxaloacetate
  47. what enviornment do C3, C4 and CAM plants survive best in?
    temperate, hot, arid.
  48. What are some strategies to maximize light?
    • steal light by growing taller and wider.
    • follow the sun (diaheliotrophism)
    • collect light through light harvesting complex
  49. what are strategies to minimize light?
    • paraheliotropism
    • reflect light with leaf hairs, waxy leaves and salt glands
    • transmit light by reducing chlroplast numbers or repositioning the chloroplasts
  50. what are 4 routes of light E
    generate reactive oxygen species, photochemical quenching, emit light, emit heat.
  51. what are the two types of photoinhibitions and explain them.
    Dynamic and Chronic. Dynamic chanes in light harvesting complex to increase heat generation. Chronic Reactive Oxygen species (ROS) induces damage to PS2 requiring disassembly and repair
  52. How does a plants combat damage from ROS?
    Carotenoids act as antioxidants and scavenge ROS and chlrophyll can tranfer E to carotenoids which do not generate ROS
  53. How does High temp effect photosynthesis in a negative and positive way?
    stimulates enzymatic processes. increases photorespiration in C3 plants and destabilizes enzymes and membranes.
  54. what are the three types of heat generation and loss
    latent, sensible, radiative
  55. Both ______ heat loss and ______ heat loss are affected by movement of air over leaf
    sensible and latent
  56. ______ is the most effective method of dissapating excess heat.
    Latent heat loss
  57. _______ is the most important factor in determining the intercellular CO2 concentration
    Stomatal resistance
  58. for many crops ________ is the primary limitation for photosynthesis
  59. _____plants become saturated for CO2 at lower concentrations due to high affinity of PEPCase for carboxylate
  60. T/F High light is more damaging at very high and very low temps
  61. High Co2 concentrations causes increased leaf temp. due to .....
    decreased latent heat loss
  62. what are the three metabolic fates of photosynthate
    starch, sucrose and E
  63. triose phosphates from carbon fixation are combined to create-______ , the precursors of starch and sucrose
    hexose phosphates.
  64. whwere is starch synthesiszed and how
    in the chloroplast. from G1P.
  65. starch produced in leaves is___________ starch
  66. T/F starch accumulates slightly faster in longer days
    false shorter days
  67. Where is sucrose synthesized and how
    in cytosol by combining G1P with F6P
  68. Sucrose from photosyntheis sources is transported to _______. define this term
    sinks. new leaves, flowers and fruits, storage roots and tubers.
  69. T/F tissues can switch between source and sink throught developement
  70. where is the sucorse transported.
  71. explain the different phloem loadings.
    Apoplastic phloem loauding uses sucrose-proton symporter. Symplastic phloem loading requres higher sucrose levels in sourse leaves or polymer trapping
  72. what are two mechanisms to seal a damaged phloem?
    • P-proteins- plug the sieve
    • callose plugs
  73. During respiration sugar is _______ to _____ and electrons are passed to _____
    oxidized CO2 O2
  74. plants uses 1 N for every how many O, C and H?
    30, 40, 60
  75. what two forms of can atmospheric N2 nitrogen be fixed into
    NO3 (nitrate) or NH3 (ammonia)
  76. what are some sources of Biologically fixed nitrogen
    animal waste, decaying matter and soil/bacteria symbionts
  77. Nitrogen assimiliation only occurs when the light reactions operate more than the carbon reactions T or F
  78. explain the skikimic acid pathway and how it relates to roundup
    plants produce tryptophane and other aromatic amino acids from the shikimac pathway and roundup blocks that pathways so tryp. is not made and plant cannot survive
  79. what are primary and seconday metabolites.
    • primary metabolites are those that are used to create AA, Nucleic acids, ATP, alkaloids, flavonoids and lignins.
    • Secondary metabolites are used to communicate with other orgaisms like fragrences and poisons
  80. what are the three classes of secondary metabolites
    termpenes, N containing compounds and phenolic coumpounds
  81. main class of nitrogen containing compounds are...
  82. what are two N containing metabolites.
    Glucosinolates and cyanogenic glycosides.
  83. what type of secondary metabolite is repsonsible for keeping herbivores away.
    N containing metaboliztes that are non protein amino acids