How they exchange gases

• Sharks use their gills to exchange gases from the water
• The gills are made of three parts:
  • The lamellae-responsible for taking oxygen out of the water and giving it to the blood
  • the gill rakers- the cartilaginous support for the gill
  • the gill arch-frame for the lamallae
  • http://www.sharkology.com/res.htmland http://www.shark-info.com/shark-anatomy/respiration/shark-respiration.htm

How it all works

1. Sharks take in water either through their mouth or the spiracle.
2. It then passes through the orobranchial cavity which leads it to the gill.
3. The water flows over the gills which includes the gill arches, and lamallae, and out of the gill slits.
4. This water flows opposite of the blood, so that the shark can extract the most oxygen possible.
5. The remaining carbon dioxide is expelled with the rest of the water.
6. Gas exchange occurs between the capillaries of the lamellae and the water.

http://www.shark-info.com/shark-anatomy/respiration/shark-respiration.htm

 

Picture from: http://new-brunswick.net/new-brunswick/sharks/parts.html

 

Which fish have an operculum?

Over the years sharks have evolved, they have not developed an operculum, a gill cover found in Osteichthyes, bony fish. Originally sharks were thought to have an average of ten gill arches, but these sharks no longer exist. Today sharks have 5 to 7 gill arches.

http://www.sharkology.com/res.html

 

Works Cited:

• "Respiration" Shark Anatomy. Shark-Info.com.Copyright ©2003-2007 Shark-Info.com <http://www.shark-info.com/shark-anatomy/respiration/shark-respiration.html>
• "Respiration" Sharkology. www.sharkology.com.<http://www.sharkology.com/res.html>
• "Parts of a shark" Respiration. Webwise Inc. <http://new-brunswick.net/new-brunswick/sharks/parts.html>
• <a href="http://science.jrank.org/pages/6114/Sharks-Respiration.html">Sharks - Respiration</a>
• "Shark," Microsoft® Encarta® Online Encyclopedia 2001 <http://encarta.msn.com>© 1997-2001 Microsoft Corporation. All rights reserved.