Sunday 10 March 2013

IDENTIFYING THE PARTS OF FLOWERS


 Flowers are the reproductive organ of plants. They carry out sexual reproduction. They have protective parts (calyx and corolla) and reproductive parts (pistil and stamen).
Lilium left to open
The calyx is made up of sepals. Sepals are usually green. The corolla is made up of petals. Petals are usually bright colours and have a strong scent. These characteristics are to attract insects that help carry out pollination. There is a large variety of shapes, sizes and colours of petals.
The stamen is the male part of the flower. Different flowers have different number of stamen. They have 2 parts. The anther and the filament. The anther produces pollen. The pollen grains contain the male sex cells. The filament is a long structure that holds the anther.
The female part of the flower is called pistil. The pistil is in the centre of the flower and is bottle shaped. The top part is called stigma and it is sticky. This is where the pollen grains stick after pollination. The long part is called the style and the bottom part is the ovary. The ovary contains the female sex cells. The shape of the pistil and stamen vary in different flowers. By observing flowers you can sometimes tell whether they are pollinated by the wind or by insects. Flowers that have very long stamen that hang out of the flower are usually pollinated by the wind. Flowers that have the stamen and pistil hidden inside the structure of the flower are pollinated by insects also flowers that have bright colours and strong scents.

We have identified the parts of flowers. For this experiment we have used lilium. Lilium are very big flowers, you can see the stamen and pistil very clearly.

We have observed the flower using a hand lens. We counted the sepals, petals, stamen and filament, also the anther, filament, stigma, style and ovary.
We touched the stigma and noticed it was sticky and touched the anther and saw how the pollen grains stuck to our finger.

After in our notebooks we wrote all the information collected in the experiment and drew a scientific diagram of the flower.
By Rodrigo Contreras - E1C
We also looked at compound flowers. If you look at a daisy, at first, you cannot see any of the parts we have studied. This is because daisies are not only one flower, in fact, they are made up of hundreds of flowers.

We opened up daisies and took a close look at each of the components. Each one is a flower, it has petals, stamen and/or pistil. Each white petal is also a flower. If you look very carefully you can see the pistil.

Students were very surprised to see that each of the components of a daisy is a flower.






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