IAA

• 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?

  In the tips of roots and shoots
• What is phototropism?

  Plant response 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 occurs when there is unilateral light on a plant?

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

  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?

  Plant response to gravity
• What happens to IAA in shoots when a plant is vertical?

  IAA diffuses down the shoot
• What happens to the shoot when it is laid on its side?

  IAA diffuses to the lower side
• What is the result of IAA diffusion in the shoot when laid on its side?

  Cells elongate on the lower side
• 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 three key stimuli that affect plant growth?

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

  • In shoots: IAA promotes cell elongation
  • In roots: IAA inhibits cell elongation
• What is the process of phototropism in plants?

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

  1. IAA produced in root tip
  2. IAA diffuses towards gravity
  3. Cells on lower side elongate
  4. Roots bend towards gravity
• How does IAA affect root growth in relation to light?

  • High IAA concentration inhibits elongation
  • Roots grow away from light source
• How does IAA affect shoot growth in relation to light?

  • High IAA concentration promotes elongation
  • Shoots grow towards light source
• What are plant hormones also known as?

  Plant growth factors
• What do plant hormones do?

  They accelerate, inhibit, or affect growth
• Where is IAA produced in the plant?

  At the apex of the stem
• How does unilateral light affect IAA distribution?

  IAA is redistributed to the shaded side
• How does IAA travel between cells?

  By diffusion
• What effect does IAA have on pH?

  It lowers the pH
• What do activated expansions do in the cell wall?

  They break bonds in the cell wall
• What causes the shoot tips to bend towards light?

  Cells on the shaded side elongate