Introduction to Reproductive anatomy:
The characteristic feature of angiosperms is flowers. Flowers show remarkable variation in form and detail and provide the most reliable external features for establishing relationships between angiosperm species. The function of the flower is to ensure the fertilization of the ovule and the development of the seed containing the fruit. The floral apparatus may arise endogenously on a twig or from the axils of the leaf (where the stalk attaches to the stem). Sometimes, as in violets, a single flower grows singly in a simple leaf-leaf axil.
In general, the plant’s flowering part is sharply separated from the leafy or vegetative part, forming a more or less elaborate branch system called the inflorescence. Flowers produce two types of germ cells. Microspores, which will divide to become pollen grains, are «male» cells and are produced in stamens (or microsporophylls). The «female» cells called megaspores, which will divide to become the egg cell (megamatogenesis), are contained in the ovule and enclosed in the carpel (or megasporophyll). Flowers may have only these parts, as in willows, where each flower has only a few stamens or two carpels. The florist offer floral delivery in houston and can provide seasonal flowers houston, tx and houston classic bouquet.
Normally, other structures are present and serve to protect the sporophyll and to form an attractive envelope for pollinators. Individual members of these surrounding structures are known as sepals and petals (or tepals in flowers such as magnolia where the sepals and petals are indistinguishable from each other). The outer covering (the mussel’s calyx) is usually green and leaf-like and serves to protect the rest of the flower, especially the bud. The inner chain (corolla of the petals) is, in general, white or brightly coloured, and more delicate in structure. It serves to attract insect or bird pollinators. Attraction is influenced by colour, smell, and nectar, which can be secreted in any part of the flower.
The same characteristics are responsible for the popularity of flowers and flowering plants among humans that attract pollinators. While most flowers are complete or bisexual (the same flower structure contains both the pollen and the ovule-producing parts), flowering plants have evolved several morphological and physiological mechanisms to reduce or prevent self-fertilization. The animal pollinators cannot easily transfer pollen to the pistil (the receptive part of the carpel) because heteromorphic flowers have short carpels and long stamens.