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Diagram of an anther in cross section. 1: Filament; 2: Theca; 3: Connective (the conducting vessels in red); 4: Pollen sac (also called sporangium) The androecium is one of the fertile cycles of flowers. The parts that make up the androecium are called stamens whose function is the generation of male gametophytes or pollen grains.
[10] (also called pollen vectors): organisms that carry or move the pollen grains from the anther of one flower to the receptive part of the carpel or pistil (stigma) of another. [11] Between 100,000 and 200,000 species of animal act as pollinators of the world's 250,000 species of flowering plant. [12]
Stamen is the Latin word meaning "thread" (originally thread of the warp, in weaving). [8]Filament derives from classical Latin filum, meaning "thread" [8]; Anther derives from French anthère, [9] from classical Latin anthera, meaning "medicine extracted from the flower" [10] [11] in turn from Ancient Greek ἀνθηρά (anthērá), [9] [11] feminine of ἀνθηρός (anthērós) meaning ...
The pollen wall protects the sperm while the pollen grain is moving from the anther to the stigma; it protects the vital genetic material from drying out and solar radiation. The pollen grain surface is covered with waxes and proteins, which are held in place by structures called sculpture elements on the surface of the grain.
Once the pollen grain is recognized and hydrated, the pollen grain germinates to grow a pollen tube. [11] There is competition in this step as many pollen grains may compete to reach the egg. The stigma plays a role in guiding the sperm to a receptive ovule, in the case of many ovules. [ 11 ]
Anther dehiscence is the final function of the anther that causes the release of pollen grains. This process is coordinated precisely with pollen differentiation, floral development, and flower opening. The anther wall breaks at a specific site.
The tapetum is a specialised layer of nutritive cells found within the anther of flowering plants, located between the sporogenous tissue and the anther wall. Tapetum is important for the nutrition and development of pollen grains and a source of precursors for the pollen coat. [ 1 ]
An anther and its filament together form a typical (or filantherous) stamen, part of the male floral organ. The typical anther is bilocular, i.e. it consists of two thecae. Each theca contains two microsporangia, also known as pollen sacs. The microsporangia produce the microspores, which for seed plants are known as pollen grains.