What is the ripened ovary of a flower called
Acorns are nuts and winged, maple whirligigs whose botanical name is samara are also fruit. Botanists classify fruit into more than two dozen different categories, only a few of which are actually fleshy and sweet. Mature fruit can be fleshy or dry. Fleshy fruit include the familiar berries, peaches, apples, grapes, and tomatoes. Rice, wheat, and nuts are examples of dry fruit. Another distinction is that not all fruits are derived from the ovary. For instance, strawberries are derived from the receptacle, while apples are derived from the pericarp, or hypanthium.
Seed coats help protect the embryo from injury and also from drying out. Seed coats can be thin and soft as in beans or thick and hard as in locust or coconut seeds.
The ovaries contain the female gamete cell, called the oocyte. The ovaries are filled with follicles. Follicles are fluid-filled structures in which the oocyte also called egg grows to maturity.
Ovary is the female reproductive part of a flower and ovules are located inside the ovary. Ovary after fertilization turns into a fruit whereas ovules turn into seeds of fruit. An ovule is a structure found inside the ovary of plants. Integuments are the two layers which cover the internal structures of the ovule. One sperm and the egg combine, forming a diploid zygote, the future embryo.
The other sperm fuses with the 2n polar nuclei, forming a triploid cell that will develop into the endosperm, which is tissue that serves as a food reserve. The zygote develops into an embryo with a radicle, or small root, and one monocot or two dicot leaf-like organs called cotyledons. This difference in the number of embryonic leaves is the basis for the two major groups of angiosperms: the monocots and the eudicots.
Seed food reserves are stored outside the embryo in the form of complex carbohydrates, lipids, or proteins. The cotyledons serve as conduits to transmit the broken-down food reserves from their storage site inside the seed to the developing embryo. The seed consists of a toughened layer of integuments forming the coat, the endosperm with food reserves, and the well-protected embryo at the center.
The fruit of the Aesculus or Horse Chestnut tree : These seeds are enclosed a protective outer covering called the seed coat, usually with some stored food. After fertilization and some growth in the angiosperm, the ripened ovule is produced. The formation of the seed completes the process of reproduction in seed plants started with the development of flowers and pollination , with the embryo developed from the zygote and the seed coat from the integuments of the ovule.
Some species of angiosperms are hermaphroditic stamens and pistils are contained on a single flower , some species are monoecious stamens and pistils occur on separate flowers, but the same plant , and some are dioecious staminate and pistillate flowers occur on separate plants.
Both anatomical and environmental barriers promote cross-pollination mediated by a physical agent wind or water or an animal, such as an insect or bird. Cross-pollination increases genetic diversity in a species. 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. Flowering plants are divided into two major groups according to the structure of the cotyledons and pollen grains, among others.
Monocots include grasses and lilies while eudicots or dicots form a polyphyletic group. However, many species exhibit characteristics that belong to either group; as such, the classification of a plant as a monocot or a eudicot is not always clearly evident.
Basal angiosperms are a group of plants that are believed to have branched off before the separation into monocots and eudicots because they exhibit traits from both groups. They are categorized separately in many classification schemes. The Magnoliidae magnolia trees, laurels, and water lilies and the Piperaceae peppers belong to the basal angiosperm group.
Examples of basal angiosperms : The a common spicebush belongs to the Laurales, the same family as cinnamon and bay laurel. The fruit of b the Piper nigrum plant is black pepper, the main product that was traded along spice routes. Notice the small, unobtrusive, clustered flowers. The red seeds of d a magnolia tree, characteristic of the final stage, are just starting to appear. Examples of basal angiosperms include the Magnoliidae, Laurales, Nymphaeales, and the Piperales.
Members in these groups all share traits from both monocot and dicot groups. The Magnoliidae are represented by the magnolias: tall trees bearing large, fragrant flowers that have many parts and are considered archaic.
Laurel trees produce fragrant leaves and small, inconspicuous flowers. The Laurales grow mostly in warmer climates and are small trees and shrubs. Familiar plants in this group include the bay laurel, cinnamon, spice bush, and avocado tree. The Nymphaeales are comprised of the water lilies, lotus, and similar plants; all species thrive in freshwater biomes and have leaves that float on the water surface or grow underwater. Water lilies are particularly prized by gardeners and have graced ponds and pools for thousands of years.
The Piperales are a group of herbs, shrubs, and small trees that grow in the tropical climates. They have small flowers without petals that are tightly arranged in long spikes. Many species are the source of prized fragrance or spices; for example, the berries of Piper nigrum are the familiar black peppercorns that are used to flavor many dishes. Plants in the monocot group are primarily identified as such by the presence of a single cotyledon in the seedling.
Here the seed is in a warm, moist environment that contains all of the mineral nutrients necessary for its growth. The tomato is a good example of this type of dispersal mechanism. Humans - Humans are by far the most efficient transporters of fruits and seeds. Noxious weeds and plant diseases, as well as valuable food and medicinal plants, have been carried from one continent to another by explorers and travelers over the past few hundred years in particular.
Most countries now have strict regulations barring the importation of plant materials, except by special permit, and some plants are not allowed across borders under any circumstances. Flowering plants produce a young plant embryo complete with stored nutrients in a compact package: the seed that develops after fertilization has occurred. Development of the embryo following fertilization is possible because of the constant flow of nutrients from the parent plant into the developing seed.
A mature seed consists of an embryonic plant and nutrients stored in either endosperm or cotyledons. Endosperm is the nutritive tissue that surrounds the embryonic plant in a seed. Cotyledons are embryonic leaves that not only have stored nutrients, they are the first leaves to emerge from the seed and, thru photosynthesis, begin manufacturing carbohydrates to feed the developing plant.
Cotyledons often absorb endosperm just prior to germination. The seed dispersal vehicle for a flowering plant is the fruit. It carries the connotation of a sweet, soft plant product.
Thus, fruits are usually regarded as a dessert food, whereas vegetables are usually considered part of the main course meal. However, the botanical definition of a fruit is quite specific — it is the ripened ovary that usually contains the seeds.
Not all fruits are sweet and soft, and many are not good to eat at all. Vegetables are considered to be the edible portion of the vegetative plant body — stem, roots, leaves, flowers. A fruit is a seed container derived from an ovary and any tissues that surround it. As such, fruits are products of flowers and therefore only occur in flowering plants.
Angiosperms flowering plants have a remarkable diversity of fruit types. Fruits are classified on the basis of characteristics of the mature ovary tissue — e. They are also classified on the basis of whether they are dehiscent or indehiscent the process of splitting open at maturity. In the former, the pericarp splits open to release the seeds i. In the latter, the pericarp encloses the seed so that the entire fruit disperses the whole fruit is the dispersal unit.
The function of fruit is two-fold: i. In fleshy fruit, the pericarp is comprised of 3 layers: exocarp - outer layer, or skin mesocarp - middle layer, often the fleshy part endocarp - inner layer that surrounds the seed.
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