Plant growth factors

• What are plant growth factors?

  Chemicals that regulate plant growth
• What is the key hormone discussed in the video?

  Auxin
• What is indole acetic acid abbreviated as?

  IAA
• What effect does high concentrations of IAA have in shoots?

  It causes cell elongation
• What effect does high concentrations of IAA have in roots?

  It inhibits cell elongation
• Where is IAA produced in plants?

  Tip of the roots and shoots
• What is phototropism?

  Response of plants to light
• Why do plants need light?

  For photosynthesis and energy production
• What happens to IAA when light is evenly distributed?

  It diffuses downwards evenly
• What happens to IAA in unilateral light conditions?

  It diffuses to the shaded side
• What is the result of IAA accumulation on the shaded side of a plant?

  Cells elongate, causing bending towards light
• What is the effect of IAA in roots regarding light?

  Roots grow away from the light source
• What is gravitropism?

  Response of plants to gravity
• How does IAA behave in shoots under gravity?

  It diffuses to the lower side
• What happens to the shoot when placed on its side in darkness?

  IAA diffuses to the lower side, causing upward bend
• What is the effect of IAA in roots regarding gravity?

  Roots bend towards gravity
• What is the term for roots growing towards gravity?

  Positive gravitropism
• What are the key stimuli that plants respond to through tropisms?

  • Light
  • Gravity
  • Water
• What are the effects of IAA in shoots and roots?

  In shoots:

  • High IAA concentration causes cell elongation

  
  

  In roots:

  • High IAA concentration inhibits cell elongation
• What is the process of phototropism in plants?

  1. IAA produced in shoot tip
  2. Light is unevenly distributed
  3. IAA diffuses to shaded side
  4. Cells on shaded side elongate
  5. Plant bends towards light
• What is the process of gravitropism in plants?

  1. IAA produced in shoot tip
  2. Plant is placed on its side
  3. IAA diffuses to lower side
  4. Cells on lower side elongate
  5. Shoot bends upwards
• What are the roles of roots in plants?

  • Absorb water and minerals
  • Anchor the plant into the ground
  • Grow away from light for stability