Examples of angiosperm in the following topics:
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- Earlier traces of angiosperms are scarce.
- A few early Cretaceous rocks show clear imprints of leaves resembling angiosperm leaves.
- Paleobotanists debate whether angiosperms evolved from small woody bushes, or were basal angiosperms related to tropical grasses.
- A few other angiosperm groups, known as basal angiosperms, are viewed as primitive because they branched off early from the phylogenetic tree.
- Angiosperms produce their gametes in separate organs, which are usually housed in a flower.
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- The adult, or sporophyte, phase is the main phase of an angiosperm's life cycle .
- As with gymnosperms, angiosperms are heterosporous.
- After fertilization and some growth in the angiosperm, the ripened ovule is produced.
- The life cycle of an angiosperm is shown.
- Double fertilization is a process unique to angiosperms.
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- Angiosperm diversity is divided into two main groups, monocot and dicots, based primarily on the number of cotyledons they possess.
- Angiosperms are classified in a single phylum: the Anthophyta.
- Modern angiosperms appear to be a monophyletic group, which means that they originated from a single ancestor.
- Examples of basal angiosperms include the Magnoliidae, Laurales, Nymphaeales, and the Piperales.
- The pollen from the first angiosperms was monosulcate, containing a single furrow or pore through the outer layer.
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- As with angiosperms, the life cycle of gymnosperms is also characterized by alternation of generations.
- Gymnosperm reproduction differs from that of angiosperms in several ways.
- Double fertilization is a key event in the life cycle of angiosperms, but is completely absent in gymnosperms.
- The male and female gametophyte structures are present on separate male and female cones in gymnosperms, whereas in angiosperms, they are a part of the flower.
- Although many angiosperms are also wind-pollinated, animal pollination is more common.
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- The lifecycle of angiosperms follows the alternation of generations.
- In the angiosperm, the haploid gametophyte alternates with the diploid sporophyte during the sexual reproduction process of angiosperms.
- As shown in this diagram of the embryo sac in angiosperms, the ovule is covered by integuments and has an opening called a micropyle.
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- Angiosperms undergo two fertilization events where a zygote and endosperm are both formed.
- Together, these two fertilization events in angiosperms are known as double fertilization .
- In angiosperms, one sperm fertilizes the egg to form the 2n zygote, while the other sperm fuses with two polar nuclei to form the 3n endosperm.
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- The fourth phylum (the Gnetophyta) are considered the closest group to angiosperms because they produce true xylem tissue.
- The wood of conifers is more primitive than the wood of angiosperms; it contains tracheids, but no vessel elements, and is, therefore, referred to as "soft wood."
- Gnetophytes are the closest relative to modern angiosperms and include three dissimilar genera of plants: Ephedra, Gnetum, and Welwitschia .
- Like angiosperms, they have broad leaves.
- Like angiosperms, but unlike other gymnosperms, all gnetophytes possess vessel elements in their xylem.
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- The name gymnosperm means "naked seed," which is the major distinguishing factor between gymnosperms and angiosperms, the two distinct subgroups of seed plants.
- Gymnosperms are older than angiosperms on the evolutionary scale.
- They are found far earlier in the fossil record than angiosperms.