BIOL 350 Lecture Notes - Lecture 15: Pericardium, Partial Pressure, Exhalation
Document Summary
Diffusion is enough for small animals (<1 mm) or even slightly larger animals if they are flat (ex. Even some larger animals have no particularly special respiratory structures. Mostly marine or aquatic because desiccation is a danger. Just (cid:271)elo(cid:449) the ski(cid:374) there"s a de(cid:374)se (cid:374)et(cid:449)ork of (cid:272)apillaries that fa(cid:272)ilitate the e(cid:454)(cid:272)ha(cid:374)ge of gasses between the circulatory system and the environment. Include catfish, leeches, lungless salamanders, borneo flathead frog. Gils are out-foldings of the body surface that are suspended in water. Most aquatic animals have some form of gills. Gills often have a total surfa(cid:272)e area that is (cid:373)u(cid:272)h greater tha(cid:374) the rest of the (cid:271)od(cid:455)"s e(cid:454)terior. Function to increase sa and therefore oxygen uptake. Correlations of activity level & gill development. Relative gill area: mackerel, toad fish. Book gills in horseshoe crabs: not actually gills, but waved through water, somewhat enclosed.
