Sharks’ Placoid Scales Have Low Water-resistance

Sharks’ Placoid scales have V-shaped grooves that reduce water drag by creating tiny vortices as the sharks swim, particularly at slow speeds. This lack of resistance allows the shark to minimize its energy output while swimming. The grooves are covered in fine projections which line up neatly side-by-side along the fin line. The placoid scales themselves are curved and overlap each other, which help to scrape off extraneous matter from the scales, making them stain-resistant.

Efficiency(Energy Saving, Resource Saving, Light):: Air or water resistance evasion

Defense/Stability:: Water repellent

Placoid scales’ lack of drag is used to create sleek swimsuit materials.

The stain resistance of placoid scales can be used to create new coating agents for ships.

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4 previous requests available
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Query Explain:

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Timer

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Memory

Peak Memory Use 9.10 MB

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Component intitailization	6.79 MB
Controller action start	6.83 MB
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Total Request Time: 1169 (ms)

Message	Time in ms	Graph
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Component initialization and startup	32.52
Controller action	56.27
Render Controller Action	76.78
» Rendering View	71.97
» » Rendering APP/views/contents/view.ctp	26.72
» » Rendering APP/views/layouts/default.ctp	25.63
» » » Rendering APP/views/elements/header.ctp	1.72
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  0Sharks’ Placoid scales have V-shaped grooves that reduce water drag by creating tiny vortices as the sharks swim, particularly at slow speeds. This lack of resistance allows the shark to minimize its energy output while swimming. The grooves are covered in fine projections which line up neatly side-by-side along the fin line. The placoid scales themselves are curved and overlap each other, which help to scrape off extraneous matter from the scales, making them stain-resistant.
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  0Electron micrograph of the scales of great white shark(s). Photo by <a href="http://australianmuseum.net.au/image/Scanning-electron-micrograph-of-the-scales-of-a-White-Shark/" target="_blank">Sue Lindsay © Australian Museum</a><br /><span style="font-size:80%;">From the Amazing Nature Database.</span>
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====

Sharks’ Placoid Scales Have Low Water-resistance

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