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The upcoming discussion will update you about the differences between Gymnosperms and Angiosperms.
Difference # Gymnosperms:
1. The sporophylls are aggregated to form cones.
2. Cones are generally unisexual, rarely bisexual.
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3. Cones do not possess perianth or sepals and petals.
4. Sporophyll bearing central axis is usually elongated.
5. Microsporophyll often contains a broad, sterile head. Distinction into anther and filament is absent.
6. Number of microsporangia per microsporophyll varies from 2 in Pinus to several hundred in Cycas.
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7. Megasporophyll is commonly woody.
8. Megasporophyll is unrolled.
9. Stigma and style are absent.
10. Ovules are not borne on a placenta.
11. Ovules lie exposed on the megasporophyll.
12. Ovules are sessile.
13. An ovule is covered by a 3-layered massive integument having a wide micropyle.
14. The female gametophyte is large and parenchymatous.
15. The female gametophyte contains distinct archegonia.
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16. Pollination is direct, that is, pollen grains directly enter the ovule and come to lie over the nucellus.
17. Male gametophyte contains one or two prothalial cells, a tube cell, a stalk cell and a body cell which divides to form 2 male gametes.
18. Only one gamete is functional as there is only one type of fertilization or generative fertilization.
19. Endosperm is a pre-fertilisation structure and represents the food laden female gametophyte.
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20. Seeds develop exposed on the megasporophyll. A fruit is never formed.
21. The embryo may contain one to several cotyledons.
Difference # Angiosperms:
1. The sporophylls are aggregated to produce flowers.
2. Flowers are generally bisexual, rarely unisexual.
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3. The flowers usually contain perianth or sepals and petals.
4. Sporophyll bearing thalamus is generally short.
5. Microsporophyll is represented by a stamen. A stamen consists of a terminal broad anther and a lower stalk or filament.
6. Number of microsporangia or pollen sacs per stamen is commonly four, rarely two.
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7. Megasporophyll is delicate.
8. Megasporophyll is rolled to form a carpel.
9. The two are present.
10. Ovules are attached to placenta.
11. Ovules occur covered inside the ovary part of the carpel.
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12. Ovules are borne on a stalk or funiculus.
13. An ovule is covered by one or two thin integuments having a narrow micro Pyle.
14. The female gametophyte is represented by seven-celled and 8- nucleate embryo sac.
15. Archegonia are absent.
16. Pollination brings the pollen grains on the special receptive surface of the megasporophyll called stigma.
17. Male gametophyte consists of a tube cell and a generative cell which divides to form two male gametes.
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18. There is double fertilisation, that is, both the male gametes are functional, one performing generative fertilisation and other vegetative fertilisation or triple fusion.
19. Endosperm is a post-fertilisation structure and represents a new triploid material.
20. Seeds develop inside the ovary part of the carpel which matures into a fruit.
21. The embryo contains one or two cotyledons.
