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| Summary |
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 Angiosperms represent the most advanced group of plants. |
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 The angiosperm plant body consists of an underground root system and an aerial shoot system. The shoot system contains vegetative parts and reproductive parts. |
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 The root serves two primary functions anchoring and absorption. |
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 There are two types of root system namely tap root system and fibrous root system. |
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 The root may show some modifications for performing specific functions. |
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 The modifications may be for storage of food or for providing mechanical support or for other vital functions. |
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 The main axis of the shoot system is called a stem. It is the ascending portion of the plant body. |
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 The stem bears distinct nodes and internodes. Branches, leaves and buds may arise at the nodal regions. |
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 The stem may be erect and strong or may be weak. The weak stem |
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| may be of a prostrate, decumbent, creeping, twining or climbing type. |
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 Apart from its regular functions, the stem may show modifications towards various other functions. |
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 Leaf is another major part of the shoot system. It is a lateral outgrowth of the main stem or a branch mainly meant for photosynthesis. |
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 The leaf has a stalk called petiole, a body called lamina, leaf apex and leaf margin. |
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 Leaves are mainly of two types simple leaves and compound leaves. Simple leaves have undivided lamina. In compound leaves, the lamina is divided into leaflets. |
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 The compound leaves can be either pinnately compound or palmately compound. Pinnately compound leaves may be unipinnate or bipinnate or tripinnate. |
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 The arrangement of leaves on the stem is known as phyllotaxy. Three types are common alternate, opposite and whorled. |
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 Leaves may sometimes be modified into tendrils or spines. |
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 The collection of flowers in a cluster on the plant is known as inflorescence. |
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 It is of two basic types racemose and cymose. In racemose type, there is an axis which keeps growing. It does not end in a flower. Flowers are found in acropetal succession. |
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 Cymose inflorescence has an axis which does not grow infinitely. It ends usually in a flower. Flowers are produced in basipetal succession. |
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 The racemose and cymose inflorescences can be distinguished into several types each. |
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 There are a few examples of inflorescences which are described as special types. |
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 Flower is the reproductive structure of a plant body. A flower has functional parts arranged in four whorls calyx, corolla, androecium and gynoecium. |
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 Calyx consists of leaf like structures called sepals while corolla consists of brightly coloured structures called petals. These two are together described as non-essential whorls of the flower which have a protective and complimentary role. |
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 Sometimes the non-essential whorls may be represented by a single structure called perianth with units called tepals. |
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 The arrangement of sepals and petals in the bud condition, is known as aestivation. It is of 4 different types such as valvate, contorted(twisted), imbricate and quincuncial. |
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 The essential whorls of a flower are represented by androecium and gynoecium. |
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 Androecium is the male whorl of the flower. It consists of functional units called stamens containing anthers where pollen grains are formed. |
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 Gynoecium is the female whorl of the flower. It consists of functional units called carpels which enclose ovules. |
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 The manner of attachment of the ovules inside the ovary is called placentation. Marginal, axile, parietal and basal types of placentation are very common. |
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 Pollination is the process by which pollen grains are transferred from the anther to the stigma of the same flower (self pollination) or another flower (cross pollination). |
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 Cross pollination is brought about by agents such as wind, water and animals, especially insects. |
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 Pollination is followed by fertilisation. In angiosperms it is described as double fertilisation and triple fusion. |
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 After fertilisation the ovule is transformed into the seed and the ovary is transformed into the fruit. |
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 Angiosperm fruits can be distinguished into three types: simple fruits, multiple fruits and composite fruits. |
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 Simple fruits are those which develop from morocarpellary or polycarpellary syncarpous gynoecium. They can be either fleshy or dry. Dry fruits can be either dehiscent or indehiscent. |
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 Multiple fruits develop from polycarpellary, apocarpous gynoecium. |
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| Composite fruits develop from the entire inflorescence. |
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