BIOL 1010 Chapter Notes - Chapter 26: Fitzroy River Turtle, Cloaca, Vocal Folds

• School: University of Manitoba
• Department: Biological Sciences
• Course: BIOL 1010
• Professor: Emily A.Mc Kinnon

Document Summary

Reptiles and mammals rely on lungs for gas exchange. I(cid:374) ge(cid:374)eral, the size of lu(cid:374)gs are (cid:272)orrelated with a(cid:374) a(cid:374)i(cid:373)al"s (cid:373)eta(cid:271)oli(cid:272) rate a(cid:374)d oxygen need. Turtles have been observed to breath through their backsides. The fitzroy river turtle (bum-breathing turtle) is one of the species capable of gas exchange called cloacal gill respiration which means that the turtle starts breathing through its bottom known as its cloaca. Most turtles have a pair of pouches coming off their large intestine called bursa that function like gills and absorb o2 from water. Using two internal muscle groups, water is pulled through the cloaca into the bursae. Cloacal gill respiration can meet up to 70% of the total oxygen demands, allowing for prolonged submersions under water which could help with potentially avoiding terrestrial predators. For these turtles, regions of the digestive tract became sufficient surfaces for gas exchange. Air enters through your nostrils and heads to your nasal cavity.