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Sunflower


Sunflower
Photo Information
Copyright: Sowmya Vallabhajosyula (sowmyav82) Silver Star Critiquer/Silver Note Writer [C: 31 W: 0 N: 36] (258)
Genre: Plants
Medium: Color
Date Taken: 2009-02-09
Categories: Flowers
Camera: Canon EOS Rebel XSi, Sigma 70-300 f/4-5.6 APO DG Macro
Exposure: f/5.6, 1/500 seconds
More Photo Info: [view]
Photo Version: Original Version
Date Submitted: 2009-02-11 8:04
Viewed: 3065
Points: 3
[Note Guidelines] Photographer's Note
Taken near Osmania University.

Courtesy: Wikipedia

The sunflower (Helianthus annuus) is an annual plant in the family Asteraceae and native to the Americas, with a large flowering head (inflorescence). The stem can grow as high as 3 meters (9 3/4 ft), and the flower head can reach 30 cm (11.8 in) in diameter with the "large" seeds. The term "sunflower" is also used to refer to all plants of the genus Helianthus, many of which are perennial plants.

Sunflowers in the bud stage exhibit heliotropism. At sunrise, the faces of most sunflowers are turned towards the east. Over the course of the day, they follow the sun from east to west, while at night they return to an eastward orientation. This motion is performed by motor cells in the pulvinus, a flexible segment of the stem just below the bud. As the bud stage ends, the stem stiffens and the blooming stage is reached.

Sunflowers in the blooming stage are not heliotropic anymore. The stem has frozen, typically in an eastward orientation. The stem and leaves lose their green color. The wild sunflower typically does not turn toward the sun; its flowering heads may face many directions when mature. However, the leaves typically exhibit some heliotropism.


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Critiques [Translate]

Perfect Close-up and bright colours!

TFS,
Prasad

Very soft focus and lovely colors. The inner ones are looking like stars arranged in a pattern. Good work.

It wud've been even more interesting, if the central portion of the flower was placed little off-center in the picture.

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