1.
Gynoecium
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Gynoecium is most commonly used as a collective term for the parts of a flower that produce ovules and ultimately develop into the fruit and seeds. The gynoecium is the innermost whorl of pistils in a flower and is surrounded by the pollen-producing reproductive organs. The term gynoecium is also used by botanists to refer to a cluster of archegonia and any associated modified leaves or stems present on a shoot in mosses. The corresponding terms for the parts of those plants are clusters of antheridia within the androecium. Flowers that bear a gynoecium but no stamens are called carpellate, flowers lacking a gynoecium are called staminate. The gynoecium is often referred to as female because it gives rise to female gametophytes, however, strictly speaking sporophytes do not have a sex, only gametophytes do. Gynoecium development and arrangement is important in research and identification of angiosperms. The gynoecium may consist of one or more separate pistils, a pistil typically consists of an expanded basal portion called the ovary, an elongated section called a style and an apical structure that receives pollen called a stigma. The ovary, is the basal portion which contains placentas. The placentas and/or ovule may be born on the gynoecial appendages or less frequently on the floral apex, the chamber in which the ovules develop is called a locule. The style, is a pillar-like stalk through which pollen tubes grow to reach the ovary, some flowers such as Tulipa do not have a distinct style, and the stigma sits directly on the ovary. The style is a tube in some plants such as lilies. The stigma, is found at the tip of the style. It is commonly sticky or feathery to capture pollen, the word pistil comes from Latin pistillum meaning pestle. A sterile pistil in a flower is referred to as a pistillode. The pistils of a flower are considered to be composed of carpels, a carpel is a theoretical construct interpreted as modified leaves bearing structures called ovules, inside which the egg cells ultimately form. A pistil may consist of one carpel, with its ovary, style and stigma, or several carpels may be joined together with a single ovary, the gynoecium may consist of one or more uni-carpellate pistils, or of one multi-carpellate pistil. The number of carpels is described by such as tricarpellate
2.
Tulip
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The tulip is a Eurasian and North African genus of perennial, bulbous plants in the lily family. It is a herb with showy flowers, of which around 75 wild species are currently accepted. The tulips centre of diversity is in the Pamir, Hindu Kush and it is a common element of steppe and winter-rain Mediterranean vegetation. A number of species and many cultivars are grown in gardens or as potted plants. Tulips are spring-blooming perennials that grow from bulbs, depending on the species, tulip plants can be between 4 inches and 28 inches high. The tulips large flowers usually bloom on scapes with leaves in a rosette at ground level, larger species tend to have multiple leaves. Plants typically have two to six leaves, some species up to 12, the tulips leaf is strap-shaped, with a waxy coating, and the leaves are alternately arranged on the stem, these fleshy blades are often bluish green in color. Most tulips produce only one flower per stem, but a few species bear multiple flowers on their scapes, the generally cup or star-shaped tulip flower has three petals and three sepals, which are often termed tepals because they are nearly identical. These six tepals are often marked on the surface near the bases with darker colorings. Tulip flowers come in a variety of colors, except pure blue. The flowers have six distinct, basifixed stamens with filaments shorter than the tepals, each stigma has three distinct lobes, and the ovaries are superior, with three chambers. The tulips seed is a capsule with a covering and an ellipsoid to globe shape. Each capsule contains numerous flat, disc-shaped seeds in two rows per chamber and these light to dark brown seeds have very thin seed coats and endosperm that does not normally fill the entire seed. Tulipanin is a found in tulips. It is the 3-rutinoside of delphinidin, the chemical compounds named tuliposides and tulipalins can also be found in tulips and are responsible for allergies. Tulipalin A, or α-methylene-γ-butyrolactone, is an allergen, generated by hydrolysis of the glucoside tuliposide A. It induces a dermatitis that is mostly occupational and affects tulip bulb sorters and florists who cut the stems, tulipanin A and B are toxic to horses, cats and dogs. The genus Tulipa was traditionally divided into two sections, Eriostemones and Tulipa, and comprises ca.76 species
3.
Flowering plant
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The flowering plants, also known as Angiospermae or Magnoliophyta, are the most diverse group of land plants, with 416 families, approx. 13,164 known genera and a total of c.295,383 known species, etymologically, angiosperm means a plant that produces seeds within an enclosure, in other words, a fruiting plant. The term angiosperm comes from the Greek composite word meaning enclosed seeds, the ancestors of flowering plants diverged from gymnosperms in the Triassic Period, during the range 245 to 202 million years ago, and the first flowering plants are known from 160 mya. They diversified extensively during the Lower Cretaceous, became widespread by 120 mya, angiosperms differ from other seed plants in several ways, described in the table. These distinguishing characteristics taken together have made the angiosperms the most diverse and numerous land plants, the amount and complexity of tissue-formation in flowering plants exceeds that of gymnosperms. The vascular bundles of the stem are arranged such that the xylem and phloem form concentric rings, in the dicotyledons, the bundles in the very young stem are arranged in an open ring, separating a central pith from an outer cortex. In each bundle, separating the xylem and phloem, is a layer of meristem or active formative tissue known as cambium, the soft phloem becomes crushed, but the hard wood persists and forms the bulk of the stem and branches of the woody perennial. Among the monocotyledons, the bundles are more numerous in the stem and are scattered through the ground tissue. They contain no cambium and once formed the stem increases in diameter only in exceptional cases, the characteristic feature of angiosperms is the flower. Flowers show remarkable variation in form and elaboration, and provide the most trustworthy external characteristics for establishing relationships among angiosperm species, the function of the flower is to ensure fertilization of the ovule and development of fruit containing seeds. The floral apparatus may arise terminally on a shoot or from the axil of a leaf, occasionally, as in violets, a flower arises singly in the axil of an ordinary foliage-leaf. There are two kinds of cells produced by flowers. Microspores, which divide to become pollen grains, are the male cells and are borne in the stamens. The female cells called megaspores, which divide to become the egg cell, are contained in the ovule. The flower may consist only of parts, as in willow. Usually, other structures are present and serve to protect the sporophylls, the individual members of these surrounding structures are known as sepals and petals. The outer series is usually green and leaf-like, and functions to protect the rest of the flower, the inner series is, in general, white or brightly colored, and is more delicate in structure. It functions to attract insect or bird pollinators, attraction is effected by color, scent, and nectar, which may be secreted in some part of the flower
4.
Ovule
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In seed plants, the ovule is the structure that gives rise to and contains the female reproductive cells. It consists of three parts, The integument forming its outer layer, the nucellus, and female gametophyte in its center, the female gametophyte—specifically termed a megagametophyte—is also called the embryo sac in angiosperms. The megagametophyte produces an egg cell for the purpose of fertilization, after fertilization, the ovule develops into a seed. In flowering plants, the ovule is located inside the portion of the called the gynoecium. The ovary of the gynoecium produces one or more ovules and ultimately becomes the fruit wall, ovules are attached to the placenta in the ovary through a stalk-like structure known as a funiculus. Different patterns of attachment, or placentation, can be found among plant species. Axile placentation, The ovary is divided into segments, with placentas in separate locules. Ventral sutures of carpels meet at the centre of the ovary, Placentae are along fused margins of carpels. Basal placentation, The placenta is at the base of the ovary on a protrusion of the thalamus, simple or compound carpel, unilocular ovary. Free-central placentation, Derived from axile as partitions are absorbed, leaving ovules at the central axis, there is only one elongated placenta on one side of the ovary, as ovules are attached at the fusion line of the carpels margins. Parietal placentation, Placentae on inner wall within a non-sectioned ovary. Two or more carpels, unilocular ovary, in gymnosperms such as conifers, ovules are borne on the surface of an ovuliferous scale, usually within an ovulate cone. In some extinct plants, megasporangia and perhaps ovules were borne on the surface of leaves, in other extinct taxa, a cupule surrounds the ovule. The ovule appears to be a megasporangium with integuments surrounding it, ovules are initially composed of diploid maternal tissue, which includes a megasporocyte. Megaspores remain inside the ovule and divide by mitosis to produce the female gametophyte or megagametophyte. The remnants of the megasporangium tissue surround the megagametophyte, megagametophytes produce archegonia, which produce egg cells. After fertilization, the contains a diploid zygote and then, after cell division begins. In flowering plants, a sperm nucleus fuses with other nuclei in the megagametophyte forming a typically polyploid endosperm tissue
5.
Petal
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Petals are modified leaves that surround the reproductive parts of flowers. They are often brightly colored or unusually shaped to attract pollinators, together, all of the petals of a flower are called a corolla. Petals are usually accompanied by another set of special leaves called sepals, the calyx and the corolla together make up the perianth. When the petals and sepals of a flower are difficult to distinguish, examples of plants in which the term tepal is appropriate include genera such as Aloe and Tulipa. Conversely, genera such as Rosa and Phaseolus have well-distinguished sepals and petals, when the undifferentiated tepals resemble petals, they are referred to as petaloid, as in petaloid monocots, orders of monocots with brightly coloured tepals. Since they include Liliales, a name is lilioid monocots. Although petals are usually the most conspicuous parts of animal-pollinated flowers, wind-pollinated species, such as the grasses, the role of the corolla in plant evolution has been studied extensively since Charles Darwin postulated a theory of the origin of elongated corollae and corolla tubes. If the petals are free from one another in the corolla, the corolla in some plants forms a tube. Petals can differ dramatically in different species, the number of petals in a flower may hold clues to a plants classification. For example, flowers on eudicots most frequently have four or five petals while flowers on monocots have three or six petals, although there are exceptions to this rule. The petal whorl or corolla may be radially or bilaterally symmetrical. If all of the petals are essentially identical in size and shape, many flowers are symmetrical in only one plane and are termed irregular or zygomorphic. In irregular flowers, other parts may be modified from the regular form. Examples of zygomorphic flowers may be seen in orchids and members of the pea family, in many plants of the aster family such as the sunflower, Helianthus annuus, the circumference of the flower head is composed of ray florets. Each ray floret is anatomically an individual flower with a large petal. Florets in the centre of the disc typically have no or very reduced petals, in some plants such as Narcissus the lower part of the petals or tepals are fused to form a floral cup above the ovary, and from which the petals proper extend. Petal often consists of two parts, the upper, broad part, similar to leaf blade, called the limb, claws are developed in petals of some flowers of the family Brassicaceae, such as Erysimum cheiri. The inception and further development of shows a great variety of patterns
6.
Sepal
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A sepal is a part of the flower of angiosperms. Usually green, sepals typically function as protection for the flower in bud, the term sepalum was coined by Noël Martin Joseph de Necker in 1790, and derived from the Greek σκεπη, a covering. Collectively the sepals are called the calyx, the outermost whorl of parts that form a flower, the word calyx was adopted from the Latin calyx, not to be confused with calix, a cup or goblet. Calyx derived from the Greek κάλυξ, a bud, a calyx, a husk or wrapping, while derived from the Greek κυλιξ, a cup or goblet. After flowering, most plants have no use for the calyx which withers or becomes vestigial. Some plants retain a thorny calyx, either dried or live, examples include species of Acaena, some of the Solanaceae, and the water caltrop, Trapa natans. In some species the calyx not only persists after flowering, but instead of withering and this is an effective protection against some kinds of birds and insects, for example in Hibiscus trionum and the Cape gooseberry. Morphologically, both sepals and petals are modified leaves, the calyx and the corolla are the outer sterile whorls of the flower, which together form what is known as the perianth. The term tepal is usually applied when the parts of the perianth are difficult to distinguish, e. g. the petals and sepals share the same color, or the petals are absent and the sepals are colorful. When the undifferentiated tepals resemble petals, they are referred to as petaloid, as in petaloid monocots, since they include Liliales, an alternative name is lilioid monocots. Examples of plants in which the term tepal is appropriate include genera such as Aloe, in contrast, genera such as Rosa and Phaseolus have well-distinguished sepals and petals. The number of sepals in a flower is its merosity, flower merosity is indicative of a plants classification. The merosity of a flower is typically four or five. The merosity of a monocot or palaeodicot flower is three, or a multiple of three, the development and form of the sepals vary considerably among flowering plants. They may be free or fused together, often, the sepals are much reduced, appearing somewhat awn-like, or as scales, teeth, or ridges. Most often such structures protrude until the fruit is mature and falls off, examples of flowers with much reduced perianths are found among the grasses. In some flowers, the sepals are fused towards the base, in other flowers a hypanthium includes the bases of sepals, petals, and the attachment points of the stamens
7.
Stigma (botany)
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The stigma is the receptive tip of a carpel, or of several fused carpels, in the gynoecium of a flower. The stigma, together with the style and ovary comprises the pistil, the stigma forms the distal portion of the style or stylodia. The stigma is composed of stigmatic papillae, the cells which are receptive to pollen and these may be restricted to the apex of the style or, especially in wind pollinated species, cover a wide surface. The stigma receives pollen and it is on the stigma that the pollen grain germinates, often sticky, the stigma is adapted in various ways to catch and trap pollen with various hairs, flaps, or sculpturings. The pollen may be captured from the air, from visiting insects or other animals, Stigma can vary from long and slender to globe shaped to feathery. Pollen is typically highly desiccated when it leaves an anther, Stigma have been shown to assist in the rehydration of pollen and in promoting germination of the pollen tube. Stigma also ensure proper adhesion of the species of pollen. The stigma is often split into lobes, e. g. trifid, the shape of the stigma may vary considerably, The style is a narrow upward extension of the ovary, connecting it to the stigmatic papillae. It may be absent in plants in the case the stigma is referred to as sessile. Styles are generally tube-like — either long or short, the style can be open with a central canal which may be filled with mucilage. Alternatively the style may be closed and this forms a nutrient rich tract for pollen tube growth. Where there are more than one carpels to the pistil, each may have a separate style-like stylodium, in Irises and others in the Iridaceae family, the style divides into three petal-like, style branches, almost to the base of the style and is called tribrachiate. These are flaps of tissue, running from the tube above the sepal. The stigma is a rim or edge on the underside of the branch, style branches also appear on Dietes, Pardanthopsis and most species of Moraea. In Crocuses, there are three divided style branches, creating a tube, hesperantha has a spreading style branch. Alternatively the style may be lobed rather than branched, gladiolus has a bi-lobed style branch. Freesia, Lapeirousia, Romulea, Savannosiphon and Watsonia have bifuracated and recurved style branches, may be terminal, subapical, lateral, gynobasic, or subgynobasic. Terminal style position refers to attachment at the apex of the ovary and is the commonest pattern, in the subapical pattern the style arises to the side slightly below the apex
8.
Pollen
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Pollen is a fine to coarse powdery substance comprising pollen grains which are male microgametophytes of seed plants, which produce male gametes. If pollen lands on a compatible pistil or female cone, it germinates, individual pollen grains are small enough to require magnification to see detail. The study of pollen is called palynology and is useful in paleoecology, paleontology, archaeology. Pollen in plants is used for transferring haploid male genetic material from the anther of a flower to the stigma of another in cross-pollination. In a case of self-pollination, this takes place from the anther of a flower to the stigma of the same flower. Pollen itself is not the male gamete, each pollen grain contains vegetative cells and a generative cell. In flowering plants the vegetative tube cell produces the pollen tube, pollen is produced in the microsporangia in the male cone of a conifer or other gymnosperm or in the anthers of an angiosperm flower. Pollen grains come in a variety of shapes, sizes. Pollen grains of pines, firs, and spruces are winged, the smallest pollen grain, that of the forget-me-not, is around 6 µm in diameter. Wind-borne pollen grains can be as large as about 90–100 µm, in angiosperms, during flower development the anther is composed of a mass of cells that appear undifferentiated, except for a partially differentiated dermis. As the flower develops, four groups of cells form within the anther. The fertile sporogenous cells are surrounded by layers of cells that grow into the wall of the pollen sac. Some of the cells grow into nutritive cells that supply nutrition for the microspores that form by meiotic division from the sporogenous cells, in a process called microsporogenesis, four haploid microspores are produced from each diploid sporogenous cell, after meiotic division. After the formation of the four microspores, which are contained by callose walls, the exine is what is preserved in the fossil record. Two basic types of microsporogenesis are recognised, simultaneous and successive, in simultaneous microsporogenesis meiotic steps I and II are completed prior to cytokinesis, whereas in successive microsporogenesis cytokinesis follows. While there may be a continuum with intermediate forms, the type of microsporogenesis has systematic significance, the predominant form amongst the monocots is successive, but there are important exceptions. During microgametogenesis, the unicellular microspores undergo mitosis and develop into mature microgametophytes containing the gametes, in some flowering plants, germination of the pollen grain may begin even before it leaves the microsporangium, with the generative cell forming the two sperm cells. Except in the case of submerged aquatic plants, the mature pollen grain has a double wall
9.
Fruit
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In botany, a fruit is the seed-bearing structure in flowering plants formed from the ovary after flowering. Fruits are the means by which angiosperms disseminate seeds, accordingly, fruits account for a substantial fraction of the worlds agricultural output, and some have acquired extensive cultural and symbolic meanings. On the other hand, in usage, fruit includes many structures that are not commonly called fruits, such as bean pods, corn kernels, tomatoes. The section of a fungus that produces spores is called a fruiting body. Many common terms for seeds and fruit do not correspond to the botanical classifications, however, in botany, a fruit is the ripened ovary or carpel that contains seeds, a nut is a type of fruit and not a seed, and a seed is a ripened ovule. Examples of culinary vegetables and nuts that are botanically fruit include corn, cucurbits, eggplant, legumes, sweet pepper, in addition, some spices, such as allspice and chili pepper, are fruits, botanically speaking. g. Botanically, a grain, such as corn, rice, or wheat, is also a kind of fruit. However, the wall is very thin and is fused to the seed coat. The outer, often edible layer, is the pericarp, formed from the ovary and surrounding the seeds, the pericarp may be described in three layers from outer to inner, the epicarp, mesocarp and endocarp. Fruit that bears a prominent pointed terminal projection is said to be beaked, a fruit results from maturation of one or more flowers, and the gynoecium of the flower forms all or part of the fruit. Inside the ovary/ovaries are one or more ovules where the megagametophyte contains the egg cell, after double fertilization, these ovules will become seeds. The ovules are fertilized in a process starts with pollination. After pollination, a tube grows from the pollen through the stigma into the ovary to the ovule, later the zygote will give rise to the embryo of the seed, and the endosperm mother cell will give rise to endosperm, a nutritive tissue used by the embryo. As the ovules develop into seeds, the ovary begins to ripen and the ovary wall, in some multiseeded fruits, the extent to which the flesh develops is proportional to the number of fertilized ovules. The pericarp is often differentiated into two or three distinct layers called the exocarp, mesocarp, and endocarp, in some fruits, especially simple fruits derived from an inferior ovary, other parts of the flower, fuse with the ovary and ripen with it. In other cases, the sepals, petals and/or stamens and style of the fall off. When such other floral parts are a significant part of the fruit, it is called an accessory fruit, since other parts of the flower may contribute to the structure of the fruit, it is important to study flower structure to understand how a particular fruit forms. There are three modes of fruit development, Apocarpous fruits develop from a single flower having one or more separate carpels
10.
Seed
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A seed is an embryonic plant enclosed in a protective outer covering. The formation of the seed is part of the process of reproduction in seed plants, Seeds are the product of the ripened ovule, after fertilization by pollen and some growth within the mother plant. The embryo is developed from the zygote and the coat from the integuments of the ovule. Seed plants now dominate biological niches on land, from forests to both in hot and cold climates. The term seed also has a meaning that antedates the above—anything that can be sown, e. g. seed potatoes. In the case of sunflower and corn seeds, what is sown is the seed enclosed in a shell or husk, many structures commonly referred to as seeds are actually dry fruits. Plants producing berries are called baccate, sunflower seeds are sometimes sold commercially while still enclosed within the hard wall of the fruit, which must be split open to reach the seed. Different groups of plants have other modifications, the stone fruits have a hardened fruit layer fused to. Nuts are the one-seeded, hard-shelled fruit of plants with an indehiscent seed. Seeds are produced in several related groups of plants, and their manner of production distinguishes the angiosperms from the gymnosperms, angiosperm seeds are produced in a hard or fleshy structure called a fruit that encloses the seeds, hence the name. Some fruits have layers of hard and fleshy material. In gymnosperms, no special structure develops to enclose the seeds, however, the seeds do become covered by the cone scales as they develop in some species of conifer. Seed production in natural plant populations varies widely from year-to-year in response to weather variables, insects and diseases, over a 20-year period, for example, forests composed of loblolly pine and shortleaf pine produced from 0 to nearly 5 million sound pine seeds per hectare. Over this period, there were six bumper, five poor, and nine good seed crops, right after fertilization, the zygote is mostly inactive, but the primary endosperm divides rapidly to form the endosperm tissue. This tissue becomes the food the young plant will consume until the roots have developed after germination, after fertilization the ovules develop into the seeds. The ovule consists of a number of components, The funicle or seed stalk which attaches the ovule to the placenta and hence ovary or fruit wall, the nucellus, the remnant of the megasporangium and main region of the ovule where the megagametophyte develops. The micropyle, a pore or opening in the apex of the integument of the ovule where the pollen tube usually enters during the process of fertilization. The chalaza, the base of the ovule opposite the micropyle, the shape of the ovules as they develop often affects the final shape of the seeds
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