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Plant Reproduction. Click to Enter. Flowers are the reproductive organs of plants. Flower Structure Pollination Fertilisation Seed Dispersal Germination Test. Flower structure. stigma. anther. style. pistil. stamen. filament. ovary. ovule.
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Plant Reproduction Click to Enter
Flowers are the reproductive organs of plants Flower Structure Pollination Fertilisation Seed Dispersal Germination Test
Flower structure stigma anther style pistil stamen filament ovary ovule Flower StructurePollination Fruit Development Seed Dispersal Germination Test
Flower Structure Quiz • What is the name of the structure labelled X in the diagram? carpel sepal X stamen peduncle Flower Structure Pollination Fertilisation Seed Dispersal Germination Test
Flower Structure Quiz • Where is pollen made? stigma sepal anther ovary Flower Structure Pollination Fertilisation Seed Dispersal Germination Test
Flower Structure Quiz • Where is the ovule found in a flower? petals style nectary ovary Flower Structure Pollination Fertilisation Seed Dispersal Germination Test
Flower Structure Quiz • Which parts of the flower are labelled below: X = style, Y = stigma X X = filament, Y = anther Y X = stigma, Y = style X = anther, Y = filament Flower Structure Pollination Fertilisation Seed Dispersal Germination Test
Pollination The pollen grain contains the male sex cell (gamete) Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Pollination is the transfer of pollen from the anther to the stigma • This is an example of cross-pollination as the pollen travels from one flower to a different flower. This is desirable in plants as it promotes variation. Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Pollen can be carried between flowers by insects or by wind Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Insect-pollinated flowers are adapted to attract insects to them to enable transfer of pollen Pollen has barbs for hooking onto insect fur nectar and a scent present Anthers positioned to rub pollen onto insects Sticky stigma to collect pollen Brightly coloured petals Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Wind-pollinated flowers are different in structure because they do not have to attract insects to them but do need to be exposed to the wind. Anthers are exposed to the wind so that pollen can easily be blown away Stigma are feathery to catch pollen carried on wind Petals are small and dull as there is no need to attract insects No scent or nectary Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Self-pollination occurs when pollen falls from the anther onto the stigma of the same flower • Self-pollination is not desirable as it reduces variation Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Flowers will prevent self-pollination by either having stigma above stamen or… Flower StructurePollination Fertilisation Seed Dispersal Germination Test
…by having stamen and stigma mature at different times. Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Click on the icons below to view the summary videos on pollination If the hyperlink does not work then copy and paste this url into a new browser window and you can watch the video then, url: http://www.youtube.com/watch?v=ge3EM8AERV0 Insect pollination (1 minute) Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Pollination Quiz • Pollination is the transfer from….? the stigma to anther style to stamen ovule to filament anther to stigma Flower StructurePollination Fruit Development Seed Dispersal Germination Test
Pollination Quiz • The two mechanisms for pollination are? Wind and water Insect and wind Insect and water Wind and birds Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Pollination Quiz • Cross-pollination… Increases variation Decreases variation Is only performed by insects Is only performed by wind Flower StructurePollination Fertilisation Seed Dispersal Germination Test
Pollination Quiz • Flowers are adapted for wind-pollination by… Having bright petals and a scent Having a nectary Having feathery stigmas Having sticky stigmas Flower StructurePollination Fruit Development Seed Dispersal Germination Test
Fertilisation and Fruit Development Flower StructurePollination Fruit Development Seed Dispersal Germination Test
Once pollination occurs a tube grows from the pollen grain down through the style to the ovule stigma style carpel ovary ovule Note: Petals not shown in order to simplify diagram Flower StructurePollination Fruit Development Seed Dispersal Germination Test
Fertilisation occurs when the male sex cell (pollen) combines with the female sex cell (ovule) and creates a zygote Flower StructurePollination Fruit Development Seed Dispersal Germination Test
Watch this short introductory video to review fertilisation (1 minute) If the hyperlink does not work then copy and paste this url into a new browser window and you can watch the video then, url:http://www.youtube.com/watch?v=pVhH2GPlckE
After fertilisation the petals, stamen and sepals fall off. The ovule turns into a seed, the fertilised egg (zygote) inside develops into an embryo plant. Cotyledon: Food store Seed coat: Protective layer Embryo shoot Embryo plant Embryo root Flower StructurePollination Fruit Development Seed Dispersal Germination Test
The ovary develops to become a fruit. Fleshy wall of the ovary (yes, you are eating an adapted ovary when you crunch into an apple! seed Flower StructurePollination Fruit Development Seed Dispersal Germination Test
