Angiosperms’ distinctive reproductive structure is the flower. The term “flower,” as it is commonly used, refers to a reproductive structure that is distinctive in colour and form.
Flowers present a seemingly limitless variety of combinations in terms of colour, size, form, and anatomical arrangement.
They range in size from tiny blossoms to enormous blooms. Individual flowers in some plants, such as poppy, magnolia, tulip, and petunia, are relatively large and showy and produced singly, whereas in others, such as aster, snapdragon, and lilac, the individual flowers may be very small and borne in a distinctive cluster known as an inflorescence. Regardless of their variety, all flowers serve the same purpose: to reproduce the species by producing seed.
What is Flower structure?
Flowers are angiosperm reproductive structures that attract insects and other pollen-bearing animals to the plant to aid in pollen dispersal. As a result, flowers are frequently colourful and showy; conversely, plants that rely on wind (rather than insects) for pollen dispersal have flowers that are more likely to be small and drab. The calyx, corolla, androecium, and gynoecium are four whorls of modified leaves that make up the flower. Each of these whorls houses one of the flower organs, namely the sepals, petals, stamens, or pistils. The stamens and pistils are the male and female reproductive organs, while the sepals and petals are not directly involved in reproduction.Furthermore, each flower has an ovary (at the base of the pistil) made of modified leaves called carpels (note that the pistil itself is sometimes referred to as the carpel). This angiosperm-only ovary encloses the ovules and develops into a fruit after fertilisation. See also Plant Classification, Angiosperms for more information on angiosperm reproduction.
Calyx
The calyx is made up of green leafy material known as sepals. Sepals protect the flower’s inner parts during development and keep them from drying out. A flower typically has the same number of sepals as petals; in fact, sepals usually alternate with the number of petals in its arrangement. However, this is not always the case. In the androecium, gynoecium, and corolla, the sepals can be fused, symmetrical, or asymmetrical. In some plant families, the sepals and petals are indistinguishable.
Androecium
The androecium is made up of the flower’s male reproductive organs, known as stamens. Each stamen has a filament at the top with an anther, the part of the stamen responsible for pollen production. The anther contains several sporangia that produce microspores. Microspores mature into pollen granules, which aid in the distribution of sperm to female reproductive organs. The number of stamens varies greatly between plant families. The stamens may emerge from the base of the pistil or be fused near the base of the petals. The anthers can be attached to the filament at the anther’s base, the back of the anther, or at a point on the anther.
Gynoecium
The gynoecium is made up of pistils or carpels that are located in the centre of the flower. The stigma and style are located at the top of the pistil, where pollen lands. When pollen granules fall to the ground, the stigma and style guide them down into the ovary. The ovary contains ovules, which form the pistil’s base. The number of pistils differs between plant families. Carpels in many plant species can be fused to form a single ovary. These same plants may also have multiple styles combined to form a single style. If this occurs, the plant will have a single pistil made up of several fused carpels.
The ovary can be positioned in one of three ways: superior, inferior, or intermediate. The ovary is considered superior if it is attached to one of the three whorls. It is inferior if it is lower than the attachment of the three whorls. The ovary is considered to be in an intermediate position if it is superior and surrounded by a receptacle. The ovary may be made up of one or more locules that house one or more undeveloped seeds known as ovules. Within the ovary, the ovules are attached to the placenta. The arrangement of the placenta differs between plant families.
Corolla
The brightly coloured petals of the flower are the most noticeable feature on most flowering plants. Flowers’ petals are frequently arranged in a circle around the centre of the flower, and this collective unit of petals is known as the corolla.
Most flowers have three other circles of structures in addition to the corolla that make up the entire flower. Most flowers have sepals on the outside of the corolla, which are small leaf-like structures that enclose the petals before the flower opens. The first circle of structures on the inside of the corolla is made up of the flower’s male reproductive organs, including the numerous stamen. The female reproductive organs are represented by the circle in the centre of the flower.
Conclusion
The calyx, corolla, androecium, and gynoecium are four whorls of modified leaves that make up the flower. Each of these whorls houses one of the flower organs, namely the sepals, petals, stamens, or pistils. The stamens and pistils are the male and female reproductive organs, while the sepals and petals are not directly involved in reproduction. A flower typically has the same number of sepals as petals; in fact, sepals usually alternate with the number of petals in its arrangement. Androecium The androecium is made up of the flower’s male reproductive organs, known as stamens. The stamens may emerge from the base of the pistil or be fused near the base of the petals. The anthers can be attached to the filament at the anther’s base, the back of the anther, or at a point on the anther.