plant hormones 1

Cards (25)

  • What environmental stimuli do plants respond to in order to survive?
    Light, gravity, and touch
  • How do plants respond to stimuli compared to animals?
    Plants respond much more slowly than animals
  • Why do plants grow their shoots towards the light?
    To maximize photosynthesis
  • Why do plants grow their roots downwards?
    To fix themselves and find water/minerals
  • What do plants rely on entirely to respond to their environment?
    Hormones
  • Do plant hormones act locally or throughout the entire organism?
    Locally
  • Which plant hormones control growth at the ends of shoots and roots?
    Auxins
  • After production in the tips, how do auxins move along the shoot or root?
    They dissolve and diffuse backwards
  • What effect do auxins have on shoots?
    Stimulate growth
  • What effect do auxins have on roots?
    Inhibit growth
  • What is the name for a plant's response to light?
    Phototropism
  • What is the name for a plant's response to gravity?
    Geotropism or gravitropism
  • Where do auxins accumulate in relation to light?
    On the shaded side
  • Where do auxins accumulate in relation to gravity?
    On the lower side
  • Are shoots positively or negatively phototropic?
    Positively phototropic
  • Are shoots positively or negatively geotropic?

    Negatively geotropic
  • Why does a shoot curve towards the light when auxin accumulates on the shaded side?
    Shaded side cells grow faster
  • How does gravity affect auxin distribution in a shoot lying horizontally?
    Auxin collects on the lower side
  • Why does a shoot curve upwards when auxin accumulates on its lower side due to gravity?
    Lower side cells grow faster
  • Are roots positively or negatively phototropic?
    Negatively phototropic
  • Are roots positively or negatively gravitropic?
    Positively gravitropic
  • What happens when roots are exposed to light?
    Auxins accumulate on the shaded side
  • Why does a root curve downwards when auxins accumulate on its lower shaded side?
    Upper side grows faster
  • If a root is horizontal, how does gravity affect its growth?
    Upper side grows faster
  • Why does the upper side of a horizontal root grow faster due to gravity?
    Auxins inhibit growth on lower side