In a flowering plant, the typical anther has two lobes, which are termed as bilobed anther. An anther has two theca. The cavity of the anther lobe is called theca. The lobes having two thecae are termed dithecous. Each theca has two pollen sacs or microsporangia. These microsporangia produce microspores that aid in the development of pollen grains.
Moreover, an anther need not be dithecous and bilobed every time. Some can be monothecous or polythecous, with single or many lobes.
The pollen unit or anther of a flowering plant is usually bilocular. This means they have two chambers or thecae. Each theca has two pollen sacs or microsporangia. If the pollen sacs are not placed together, the formation of theca is disturbed. Thus, there can be no theca.
Often, the theca is separated by a groove that runs longitudinally.
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Frequently Asked Questions
What is the structure of an anther?
The male reproductive part of the flowering plant has stamens. These stamens are filamentous structures that support the anther. The anther is a lobe-like structure that is joined by connective tissue. These anthers are pollen-producing parts of the flower.
What is the difference between a lobe and theca of an anther?
The flat projection from the anther is termed as lobe. A typical anther is a bilobed structure. An anther has two theca. Also, this theca acts as a cavity or chamber for the lobes.
How many thecae are present in a bilobed anther?
An anther having two lobes is termed as a bilobed anther. Usually, an anther has two theca structures. Each theca produces two microsporangia. Thus, dithecous anther produces four microsporangia.
What is a tetrasporangiate anther?
An anther having four pollen sacs or microsporangia is termed as a tetrasporangiate anther. Each anther lobe produces two pollen sacs, and thus it is an integral part of the bilobed anther. A typical anther is a tetrasporangiate structure.