plant hormones

• Where is auxin found in a plant?

  in tips of stems and roots
• What is auxin?

  A plant hormone
• What does auxin do?

  Controls plant growth in response to light and gravity
• What is plant growth in response to light called?

  Phototropism
• What is plant growth in response to gravity called?

  Gravitropism
• Where does enlargement occur in plants

  behind the tips
• If the tip of a shoot is removed it will...

  stop growing
• What does ethene stimulate in fruit?

  ripening
• extra auxin will do what in roots?

  inhibit growth
• extra auxin will do what in shoots?

  promote growth
• When shoots are exposed to light, what side will accumulate more auxin?

  shaded side
• will shaded side or exposed side elongate faster?

  shaded
• Shoots grow away from gravity
• roots grow towards gravity
• when a shoot is growing sideways gravity produces what?

  unequal auxin
• if a root is growing sideways there will be more auxin on the..

  lower side
• what is a gibberellin?

  Plant hormone
• What does the gibberellin hormone stimulate?

  seed germination

  stem growth

  flowering

  growing larger fruit
• What hormone does weed killer, rooting powder and tissue culture involve?

  auxin
• how does weedkiller kill weeds?

  disrupting normal growth patterns
• Selective weedkillers only effect what kind of plants?

  Broad-leaved plants
• What kind of leaves do grasses and cereals have that make them different to weeds?

  narrow leaves
• What is a cutting?

  A bit of plant that has been cut off
• What do we add to cuttings to make them grow roots rapidly?

  rooting powder
• What does rooting powder enable growers of plants to produce lots of?

  Clones
• What is tissue culture in plants?

  Growing clones of a plant from a few of its cells
• gibberellins control dormancy to make them germinate at unusual times of year
• ripening can be delayed in transit by using chemicals that block ethenes effects