1. B8: Reproduction in Plants

2. Identify and draw the parts of an insect- pollinated flower1 8
Stamen 9 2 7 6 3 5 4

3. Insect-pollinated flower parts
Function
Sepal
Leaf-like structures that protect the flower bud
Petals
Brightly coloured and scented to attract insects
Stamen
The male sex organ
Anther
Part of the stamen where pollen is made
Filament
The stalk which holds the anther
Carpel
Female sex organ
Stigma
Top of the carpel where the pollen lands
Style
Pollen travels down here to reach the ovary
Ovary
Contains the ovules
Ovule
Contains the female gamete (egg cell)

4. Identify and draw the parts of a wind-pollinated flower
Sepal
Anther
Ovary
Stigma
Filament
Stamen 1 5 2 4 6 3

5. Differences between insect- and wind-pollinated flowers
Feature
Insect-pollinated
Wind-pollinated
Description
Reason
Petals
Large, bright
To attract insects
Dull or absent
No need to attract insects
Scent
Often sweet
No scent
Nectar
In nectary
No nectar
Pollen quantity
Moderate
Less wastage
Great quantities
Most pollen does not reach another flower
Pollen
Sticky or spiky
To stick to insects
Light and smooth
So it can blow in the wind
Anthers
Firm and inside the flower
To brush against insects
Loosely attached and dangle out
To release pollen into the wind
Stigma location
Inside the flower
Insect will brush against it
Hangs outside the flower
To catch drifting pollen
Stigma structure
Sticky coating
Pollen will stick to it
Feathery or net-like
To catch the drifting pollen

6. Pollination
The transfer of pollen grains from the anther to a stigma of a plant of the same species
Insects and wind are 2 agents of pollination
Birds and bats and some mammals are others
When the anther is ripe, it will split, releasing the pollen
Insect-pollinated flowers provide an incentive for bees etc to visit the flower
The bee feeds on the nectar stored at the base of the flower, and gets coated in pollen from the anther
When the bee visits anther flower for more nectar it will brush the second stigma with pollen – pollination occurs
Pollination in action
pollination

7. Fertilisation
Once the pollen lands on the stigma, the grains start to grown down the style towards the ovary
The nucleus of the male gamete fuses with the egg cell nucleus in the ovule – fertilisation has occurred.
The zygote divides and grows into the embryo.
The ovule becomes the seed
The ovary is the fruit with the seeds inside
Seed production

8. Germination The growth of the embryo, forming a radicle (small root)
Water, oxygen and a suitably warm temperature are needed for germination
water swells the seed, breaking the seed coat and allowing the cells to develop vacuoles and swell
swelling of the seeds causes the radicle to grow
water allows the embryo to access the food stores in the seed
Oxygen is required for respiration to provide energy
the warmer temperature is needed for the enzymes to work efficiently
Seed growth