Significant Differences between Anther and Stigma: definition, meaning

Definition Of Anther And Stigma

Sexual reproduction in plants occurs through reproductive structures, most of which contain both the male and female organs. The anther is a male reproductive organ that produces and liberates the pollen from the plant, while the stigma is part of the pistil and is a female structure that receives the pollen during fertilisation.

These structures are of immense importance to a plant biologist since they form the core of the plant life cycle, notably the reproductive cycle, by being responsible for carrying genetic material and giving rise to seeds. This is used in agriculture, horticulture, and plant breeding since manipulation of these processes will result in better crop yields and varieties of plants.

Also read

• Sexual Reproduction In Flowering Plants
• Polyembryony
• Apomixis

What Is An Anther?

An anther is the pollen-producing component of a stamen, or the male reproductive part of a flower. Usually found at the end of a slender stalk known as the filament, the anther is typically bilobed and has pollen sacs (microsporangia) where pollen grains are formed. These pollen grains contain the male gametes (sperm cells) involved in fertilisation. Upon maturity, the anther discharges the pollen, which gets transferred to the stigma of a flower by wind, water, or pollinators, starting the process of pollination.

Structure Of Anther

The anther is one of the most important parts of the stamen, the male reproductive structure of flowering plants. Its job is to generate and discharge pollen grains containing the male gametes that will be used for fertilisation. The anther is commonly bilobed in structure, with each lobe bearing two pollen sacs or microsporangia. These sacs are where microsporogenesis, the production of the pollen grain, takes place. The structure of the anther is discussed below:

• Anther is usually bilobed, i.e., having two lobes.
• There are two pollen sacs or microsporangia (a total of four for one anther) within each lobe.
• The pollen sacs bear and store pollen grains that contain the male gametes.
• The internal sterile tissue dividing the pollen sacs is referred to as the connective.
• Another is connected to the filament of the stamen, making up the male reproductive unit.
• The exterior anther wall consists of several layers that are the epidermis, endothecium, middle layers, and tapetum (nutritive to pollen in development).

Another serves primarily for pollen generation and storage. The mature pollen is released from the pollen sacs and spread, taken then to the stigma, fertilising it in the process.

What Is A Stigma?

A stigma is the uppermost region of the pistil, the flowering plant's female reproductive organ. It is the surface on which pollen grains land during pollination. Sticky or feathery in nature, the stigma is particularly designed to catch and retain pollen efficiently. After compatible pollen has landed on the stigma, it germinates to produce a pollen tube that extends down the style to the ovule for fertilisation. The position and structure of the stigma are essential to facilitate proper reproduction in flowering plants.

Structure Of Stigma

The stigma is a part of the female reproductive organ in angiosperms and plays an essential role in pollination. Located at the top of the pistil, it is the receptive surface for pollen grains. Its form is particularly shaped to trap and retain pollen, most often sticky, feathery, or glandular. When compatible pollen comes in contact with the stigma, it triggers germination and development of the pollen tube, which results in effective fertilisation. Thus, the stigma plays an important role in maintaining that only the appropriate kind of pollen takes part in reproduction.

• The stigma is the outermost portion of the pistil (female reproductive structure) within a flower.
• It is usually sticky or feathery to efficiently trap and capture pollen grains.
• Above the style, it creates the pollination receptive surface.
• The stigma surface can be wet (moist) or dry, based on the plant species.
• It usually includes specialised cells or secretions that helps in the recognition of compatible pollen and triggering germination.

Differences Between Anther And Stigma

The anther is a part of the male reproductive organ (stamen) and is responsible for producing and releasing pollen grains. The stigma is part of the female reproductive organ (pistil) and serves as the receptive site for pollen during pollination. While the anther helps in pollen dispersal, the stigma makes sure pollen captured and supports its germination.

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