Plant hormones

• What is auxin?

  The plant hormone that controls growth near the tips of shoots and roots
• What does auxin control?

  Plant growth in response to light (phototropism) and gravity (gravitropism or geotropism)
• Where is auxin produced?

  In the tip, it enlarges the plants just before the tip
• How does auxin effect the roots and shoots?

  It inhibits growth in the roots, but it increases growth in the shoots
• What happens when the shoots grow towards the light?

  Auxin accumulates on the side of the shoot in the shade, this makes the cells grow faster on the shaded side so the shoot bends toward the light
• What happens when the shoots grow away from gravity?

  Gravity produces an unequal distribution of auxin with more on the lower side, this causes the lower side to grow faster and bend the shoot upwards
• What happens when the roots grow towards gravity?

  A root that grows on its side will have more auxin on the lower side, auxin inhibits root growth so the cells on top will grow faster and the root will bend down