Explain the structure of hibiscus flower ?

for practical

Explain the structure of hibiscus flower ?
If you tear away one side of the flower at the right, inside you'll find the item shown at the left. When you see what you see there, you know you have an hibiscus flower. Remembering from our our Standard Blossom that a flower's male stamens are composed of the pollen-producing anther atop a stemlike filament, it will mean something to you that those roundish, yellow things in the picture at the left are anthers that have opened and are discharging yellow pollen. Notice that, just like in our Standard Blossom, each anther is held aloft by a slender, pink filament, but unlike the structure of our Standard Blossom each filament is then attached to a pale, pink cylinder, known as a staminal column or "stamen tube." At the right you see a close-up of the staminal column showing how each stamen is attached to it.





At the top of the picture showing the staminal column notice how there are several recurved, red things looking like very slender fingers with knobby tips poking through the stamens. If you carefully cut away one side of the staminal column you'll find that it is an empty cylinder, and that inside it is the long, slender style shown in the much-magnified picture at the left. In the close-up at the left, notice how the style separates into five style-branches, and each style branch ends in a roundish stigma. That's what looks like recurved, slender fingers in the picture of the staminal column. In the picture at the left you can see individual pollen grains sticking to the stigma and style branches, and of course those pollen grains carry the male sex germ.





So, if you find a flower with this particular arrangement of flower parts -- a staminal tube surrounding a long, slender style that's split into slender, spreading branches at the top -- you'll know you have an hibiscus flower!!
Reply:Flowering plants heterosporangiate (producing two types of reproductive spores). The pollen (male spores) and ovules (female spores) are produced in different organs, but the typical flower is a bisporangiate strobilus in that it contains both organs.





A flower is regarded as a modified stem with shortened internodes and bearing, at its nodes, structures that may be highly modified leaves.[1] In essence, a flower structure forms on a modified shoot or axis with an apical meristem that does not grow continuously (growth is determinate). The stem is called a pedicel, the end of which is the torus or receptacle. The parts of a flower are arranged in whorls on the torus. The four main parts or whorls (starting from the base of the flower or lowest node and working upwards) are as follows:


Calyx – the outer whorl of sepals; typically these are green, but are petal-like in some species.


Corolla – the whorl of petals, which are usually thin, soft and colored to attract insects that help the process of pollination.


Androecium (from Greek andros oikia: man's house) – one or two whorls of stamens, each a filament topped by an anther where pollen is produced. Pollen contains the male gametes.


Gynoecium (from Greek gynaikos oikia: woman's house) – one or more pistils. The female reproductive organ is the carpel: this contains an ovary with ovules (which contain female gametes). A pistil may consist of a number of carpels merged together, in which case there is only one pistil to each flower, or of a single individual carpel (the flower is then called apocarpous). The sticky tip of the pistil, the stigma, is the receptor of pollen. The supportive stalk, the style becomes the pathway for pollen tubes to grow from pollen grains adhering to the stigma, to the ovules, carrying the reproductive material.


Although the floral structure described above is considered the "typical" structural plan, plant species show a wide variety of modifications from this plan. These modifications have significance in the evolution of flowering plants and are used extensively by botanists to establish relationships among plant species. For example, the two subclasses of flowering plants may be distinguished by the number of floral organs in each whorl: dicotyledons typically having 4 or 5 organs (or a multiple of 4 or 5) in each whorl and monocotyledons having three or some multiple of three. The number of carpels in a compound pistil may be only two, or otherwise not related to the above generalization for monocots and dicots.





In the majority of species individual flowers have both pistils and stamens as described above. These flowers are described by botanists as being perfect, bisexual, or hermaphrodite. However, in some species of plants the flowers are imperfect or unisexual: having only either male (stamens) or female (pistil) parts. In the latter case, if an individual plant is either male or female the species is regarded as dioecious. However, where unisexual male and female flowers appear on the same plant, the species is considered monoecious.





Additional discussions on floral modifications from the basic plan are presented in the articles on each of the basic parts of the flower. In those species that have more than one flower on an axis—so-called composite flowers— the collection of flowers is termed an inflorescence; this term can also refer to the specific arrangements of flowers on a stem. In this regard, care must be exercised in considering what a ‘‘flower’’ is. In botanical terminology, a single daisy or sunflower for example, is not a flower but a flower head—an inflorescence composed of numerous tiny flowers (sometimes called florets). Each of these flowers may be anatomically as described above. Many flowers have a symmetry, if the perianth is bisected through the central axis from any point, symmetrical halves are produced - the flower is called regular or actinomorphic e.g. rose or trillium. When flowers are bisected and produce only one line that produces symmetrical halves the flower is said to be irregular or zygomorphic. e.g. snapdragon or most orchids.
Reply:Floral structure:


A family of local economic importance in that Cotton is a member. Perianth, often subtended by a calyx-like whorle of bracts (epicalyx), of 5 sepals and petals and an androecium of numerious stamens that are fused to form a 'filament tube' around the style. Carpel number ranges from 5 to numerous but always syncarpous and, in Hibiscus, 5 carpels as indicated by 5 'capitate' stigmas.