Plant tropism and other movements

  1. Etiolation
    a) growth response to amount of light

    b) plants have grown in low light or dark
  2. (etiolation) description- plants have grown in low light or dark
    • a) leaves less green
    • b) stems longer
    • c) smaller leaves
  3. Etiolation-internal factors
    • a) affects amount of auxin. Makes stems longer
    • b) no chlorophyll formed

    *auxin could be interacting with (GA) Gibberellic-acid
  4. Tropisms
    • a) growth response from one direction
    • b) permanent, unless they change direction
  5. Phototropism
    • a) light from one direction
    • b) internal factor is Auxin (IAA)
  6. Phototropism-( internal factor is auxin)
    • a) auxin moves away from light
    • b) more auxin, larger cells
  7. Gravitoprism
    a) growth response due to gravity

    b) internal factors; auxin, GA, and others?
  8. Roots positive gravitopism
    roots grow downward, along with gravity
  9. Thigmotropism
    a) growth response to touch

    b) internal factors: ethylene and Auxin
  10. (thigmotropism) a) growth response to touch
    1.) direct: touch, vine touching a stem

    2.) indirect: wind, stems shorter, wider
  11. Nastic movements
    • a) nondirectional
    • b) reversible
    • c) changes in turgor pressure
  12. Nastic Movements- nondirectional
    doesnt come from one direction
  13. Seismonasty
    • a) plants parts moved when touched
    • b) rapid changes
    • c) internal factors: turgor pressure

    ex) venus fly trap
  14. Sleep movements
    a) leaves and flowers open and close

    b) internal factors: internal clock and turgor pressure
  15. Photoperiodism
    • a) plants respond to seasonal changes
    • b) daylength and red or red far light
    • c) internal factors: Phytochrome
    • d) photoperiodism can effect flowering time or session (some plants)
  16. Short day plants
    • -plants bloom when days are shorter
    • *in fall or winter

    -need a minimum # if hours of light, less than 8 hours
  17. Long day plants
    • -plant bloom when day are longer
    • *in summer

    need a max # of hours of light, +16
  18. day neutral plants
    -flowering time not determined by day
Card Set
Plant tropism and other movements