ENWC314 Lecture Notes - Lecture 12: Lungless Salamander, Air Sacs, Malpighian Tubule System

• School: University of Delaware
• Department: Entomology and Wildlife Conservation
• Course: ENWC314
• Professor: York Joanna

Document Summary

Countercurrent exchange: pro(cid:272)ess of e(cid:454)(cid:272)ha(cid:374)gi(cid:374)g solutes, heat, et(cid:272) (cid:271)et(cid:449)ee(cid:374) t(cid:449)o (cid:862)(cid:272)urre(cid:374)ts(cid:863) passi(cid:374)g i(cid:374) opposite directions, plays a role in gas exchange, maintaining temperature, and waste excretion (kidneys) Some heat goes from the stream going out to the stream coming could be water or blood in; conserves energy and heat. Fish respiration: gills are site of exchange, carbon dioxide from blood is exchanged with oxygen from water, occurs via a countercurrent exchange in gills, tuna gills. More sa-more efficient structure of gills is critical red color from hemoglobin. Marine animal respiration: flat- and tape-worms: diffusion across body wall, crabs, bivalves, snails: across gills, mammals: via lungs, must be done quickly/ efficiently due to long diving times. Spend long periods of time under water: dolphins exchange 80% of lung capacity per breath. (humans ~17%) Important: surface across which gases are exchanged must be moist. Gas exchange systems in terrestrial animals: skin, tracheae, lungs, external gill.