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'''Stamen'''
= Stamen =


The '''stamen''' is the pollen-producing reproductive organ of a flower. Collectively the stamens form the androecium.
[[File:Amaryllis_stamens_aka.jpg|thumb|right|Stamens of an Amaryllis flower]]


== Morphology and terminology ==
The '''stamen''' is the pollen-producing reproductive organ of a [[flower]]. Collectively, the stamens form the ''androecium'' of a flower. The stamen typically consists of a stalk called the ''filament'' and an ''anther'', which contains [[microsporangia]].
A stamen typically consists of a stalk called the filament and an anther which contains microsporangia. Most commonly anthers are two-lobed and are attached to the filament either at the base or in the middle area of the anther. The sterile tissue between the lobes is called the connective.
 
== Structure ==
 
[[File:Stamen_(PSF).png|thumb|left|Diagram of a stamen]]
 
A typical stamen consists of two main parts:
 
* '''Filament''': The filament is a slender stalk that supports the anther. It positions the anther in a way that facilitates the transfer of [[pollen]] to the [[pistil]] or to pollinators.
 
* '''Anther''': The anther is the part of the stamen where pollen is produced. It usually consists of two lobes, each containing two microsporangia. The microsporangia are the sites of pollen development.


== Function ==
== Function ==
A typical, entomophilous (insect-pollinated) stamen consists of a pollen-producing anther attached to a filament. The pollen is released when the anther's two lobes open up. This process is called dehiscence.


== Types of stamen ==
The primary function of the stamen is to produce and release pollen. Pollen grains contain the male gametes necessary for [[fertilization]] in plants. During the process of [[pollination]], pollen is transferred from the anther to the stigma of a flower, leading to fertilization and the production of seeds.
Stamens can be categorized in a number of ways:  
 
* By attachment to the perianth
== Variations ==
* By number
 
* By length
[[File:Hippeastrum-1.jpg|thumb|right|Stamens of a Hippeastrum flower]]
* By anther attachment
 
* By anther dehiscence
Stamens can vary greatly in size, shape, and number among different plant species. Some flowers have a single stamen, while others may have numerous stamens. The arrangement and morphology of stamens can be important for the identification of plant species.
* By pollen release
 
== Development ==
 
Stamens develop from the floral meristem and are considered modified [[leaves]]. During development, the stamen primordia differentiate into the filament and anther. The anther undergoes meiosis to produce haploid pollen grains.
 
== Pollination ==
 
[[File:Closeup_of_Lilium_'Stargazer'_(the_'Stargazer_lily').jpg|thumb|left|Close-up of Lilium 'Stargazer' showing stamens]]
 
Pollination is the process by which pollen is transferred from the anther to the stigma. This can occur through various mechanisms, including wind, water, and animal pollinators such as insects and birds. The structure and position of stamens can influence the method of pollination.
 
== Related Structures ==
 
[[File:Mature_flower_diagram.svg|thumb|right|Diagram of a mature flower showing stamens]]


== Evolution ==
* '''[[Pistil]]''': The female reproductive part of a flower, consisting of the stigma, style, and ovary.
The stamen is thought to have originated in the sporangia of the ancient, extinct group of plants known as the progymnosperms.
* '''[[Petal]]''': Often colorful parts of a flower that attract pollinators.
* '''[[Sepal]]''': Protective leaf-like structures that enclose the flower bud.


== See also ==
== Examples ==
* [[Androecium]]
 
* [[Anther]]
[[File:Antera_Lilium.jpg|thumb|left|Anther of a Lilium flower]]
* [[Filament]]
 
* '''[[Lilium]]''': The lily flower has prominent stamens with large anthers that are often visible and produce abundant pollen.
* '''[[Hippeastrum]]''': Known for its large, showy flowers with long stamens.
* '''[[Phalaenopsis]]''': Orchids with unique stamen structures adapted for specific pollinators.
 
== Related Pages ==
 
* [[Pollination]]
* [[Flower]]
* [[Flower]]
* [[Pollen]]
* [[Reproduction in plants]]


== References ==
[[File:Phalaenopsis_orchid-Stipe.jpg|thumb|right|Stipe of a Phalaenopsis orchid]]
<references />


== External links ==
== Gallery ==
* [http://www.britannica.com/EBchecked/topic/562618/stamen Britannica Online Encyclopedia]


[[Category:Floral parts]]
[[Category:Plant anatomy]]
[[Category:Plant reproduction]]
{{stub}}
<gallery>
<gallery>
File:Amaryllis_stamens_aka.jpg|Stamen
File:Penta_anther.jpg|Anther of a Penta flower
File:Stamen_(PSF).png|Stamen
File:Hippeastrum-1.jpg|Stamen
File:Closeup_of_Lilium_'Stargazer'_(the_'Stargazer_lily').jpg|Stamen
File:Mature_flower_diagram.svg|Stamen
File:Antera_Lilium.jpg|Stamen
File:Phalaenopsis_orchid-Stipe.jpg|Stamen
File:Penta_anther.jpg|Stamen
File:Lily_stamens.jpg|Stamen
File:蘇利南合歡_Calliandra_surinamensis_20210529152746_02.jpg|Stamen
File:香蘋婆_Sterculia_foetida_20210409164154_01.jpg|Stamen
File:銀樺_Grevillea_robusta_20210411152016_14.jpg|Stamen
</gallery>
</gallery>
[[Category:Plant anatomy]]
[[Category:Reproductive system]]

Latest revision as of 14:19, 21 February 2025

Stamen[edit]

Stamens of an Amaryllis flower

The stamen is the pollen-producing reproductive organ of a flower. Collectively, the stamens form the androecium of a flower. The stamen typically consists of a stalk called the filament and an anther, which contains microsporangia.

Structure[edit]

Diagram of a stamen

A typical stamen consists of two main parts:

  • Filament: The filament is a slender stalk that supports the anther. It positions the anther in a way that facilitates the transfer of pollen to the pistil or to pollinators.
  • Anther: The anther is the part of the stamen where pollen is produced. It usually consists of two lobes, each containing two microsporangia. The microsporangia are the sites of pollen development.

Function[edit]

The primary function of the stamen is to produce and release pollen. Pollen grains contain the male gametes necessary for fertilization in plants. During the process of pollination, pollen is transferred from the anther to the stigma of a flower, leading to fertilization and the production of seeds.

Variations[edit]

Stamens of a Hippeastrum flower

Stamens can vary greatly in size, shape, and number among different plant species. Some flowers have a single stamen, while others may have numerous stamens. The arrangement and morphology of stamens can be important for the identification of plant species.

Development[edit]

Stamens develop from the floral meristem and are considered modified leaves. During development, the stamen primordia differentiate into the filament and anther. The anther undergoes meiosis to produce haploid pollen grains.

Pollination[edit]

Close-up of Lilium 'Stargazer' showing stamens

Pollination is the process by which pollen is transferred from the anther to the stigma. This can occur through various mechanisms, including wind, water, and animal pollinators such as insects and birds. The structure and position of stamens can influence the method of pollination.

Related Structures[edit]

Diagram of a mature flower showing stamens
  • Pistil: The female reproductive part of a flower, consisting of the stigma, style, and ovary.
  • Petal: Often colorful parts of a flower that attract pollinators.
  • Sepal: Protective leaf-like structures that enclose the flower bud.

Examples[edit]

Anther of a Lilium flower
  • Lilium: The lily flower has prominent stamens with large anthers that are often visible and produce abundant pollen.
  • Hippeastrum: Known for its large, showy flowers with long stamens.
  • Phalaenopsis: Orchids with unique stamen structures adapted for specific pollinators.

Related Pages[edit]

Stipe of a Phalaenopsis orchid

Gallery[edit]