Plant hormones

• What is the focus of today's video?

  The role of auxins in plant responses
• How do plants respond to stimuli compared to animals?

  Plants respond more slowly than animals
• How do plants maximize photosynthesis?

  By growing shoots towards light
• What do plants sense to grow their roots downwards?

  Gravity
• What do some plants sense to climb around objects?

  Touch
• How do plants rely on hormones compared to animals?

  Plants rely entirely on hormones, no nervous system
• What are the hormones that control plant growth called?

  Auxins
• Where do auxins accumulate in shoots?

  On the shaded side
• What is the effect of auxins in shoots?

  They stimulate growth
• What is phototropism?

  A response to light
• What is geotropism?

  A response to gravity
• What is the direction of growth for shoots in response to light?

  Towards the light
• What is the direction of growth for shoots in response to gravity?

  Away from the ground
• How do auxins affect shoot curvature towards light?

  They accumulate on the shaded side
• What happens to cells on the shaded side of a shoot?

  They grow faster than sunny side cells
• How do auxins affect root growth in response to light?

  They inhibit growth on the shaded side
• What is the direction of root growth in response to light?

  Away from the light
• How do auxins affect root curvature in response to gravity?

  They accumulate on the lower side
• What are the three plant hormones discussed in the video?

  Auxin, gibberellin, and ethylene
• What happens to the upper side of roots when auxins inhibit growth?

  It grows faster than the lower side
• What is the primary function of auxin in plants?

  It stimulates plant growth
• How can auxin be used in tissue culture?

  To stimulate growth of plant clones
• What happens when cuttings are treated with auxin powder?

  They produce roots and grow into new plants
• Why can auxin be used as a weed killer?

  It disrupts growth patterns in broad-leaved plants
• What type of plants are most commercial crops?

  Narrow-leaved plants
• What are the three main uses of gibberellin?

  Controlling dormancy, inducing flowering, growing larger fruit
• What are the key responses of plants to light and gravity?

  • Phototropism: shoots grow towards light
  • Geotropism: roots grow towards gravity
• What is dormancy in seeds?

  Period before growth starts
• How does gibberellin help farmers?

  It induces germination out of season
• How does gibberellin affect flowering in plants?

  It can induce flowering on demand
• How does gibberellin help with seedless fruit varieties?

  It ensures their fruits grow larger
• What is the role of ethylene in fruit ripening?

  It stimulates the ripening process
• Why is controlling fruit ripening important for transportation?

  To ensure fruit is ripe upon arrival
• How do farmers use ethylene during fruit transport?

  To ripen fruit after transport
• How do auxins function differently in shoots and roots?

  • In shoots: Auxins stimulate growth
  • In roots: Auxins inhibit growth
• How does ethylene work at the cellular level?

  It stimulates an enzyme for ripening
• What are the commercial uses of auxin?

  • Stimulating growth in tissue culture
  • Promoting root development in cuttings
  • Selective weed control in broad-leaved plants
• What are the commercial uses of gibberellin?

  • Controlling seed dormancy
  • Inducing flowering on demand
  • Promoting larger fruit growth
• What are the commercial uses of ethylene?

  • Stimulating fruit ripening
  • Controlling ripening during transport
  • Enhancing the ripening process at the cellular level