Sexual reproduction in plants (Bangor)

Question 1

What are the characteristics of a wind pollinated flower?

Answer 1

• Petals small and green or no petals at all.
  The flowers are located above the leaves, or
  produced in early spring to give maximum
  advantage from wind currents, without
  interference from leaves.
• The stigmas are large and feathery and hang
  outside the flower to catch airborne pollen in
  wind currents.
• Large anthers suspended outside the flower to
  release pollen grains into wind currents.
• Vast numbers of small, light, smooth-walled
  pollen grains are produced which are easily
  carried by the wind.

Question 2

What are the characteristics of an insect pollinated flower?

Answer 2

• Large and brightly coloured petals, often with
  guidelines to the nectaries to attract the insect
  pollinators.
• The stigma is sticky to trap pollen grains and is
  inside the flower, where insects rub against it
  thus causing pollen to be deposited.
• Anthers on rigid filaments, inside the flower:
  where insect must rub against them. This
  increases chance of pollen being deposited on
  insect body.
• The pollen grains are large with spiky walls
  which stick to insect bodies.

Question 3

what is the function of the 4 pollen sacs in the anther?

Answer 3

Contains a large number of diploid (2n) mother cells produced by mitosis

Question 4

what is the function of the area if dehiscence in the anther (stomium)

Answer 4

walls of the anther pull apart and release the pollen grains (pollen sacs go inside out)

Question 5

Function of the Tapetum?

Answer 5

inner wall of cells that provide nutrients to the developing grains. (layer below the fibrous layer)