BIOL108 Lecture Notes - Lecture 34: Copper Loss, Polyphyly, Mechanoreceptor

• School: University of Alberta
• Department: Biology (Biological Sciences)
• Course: BIOL108
• Professor: Lien Luong

Document Summary

Hair & fat also help with thermoregulation. Energy & food expensive; requires a lot of them to maintain heat via metabolism. Dentition much more differentiated than reptile dentition; heterodont. Greater diversity in tooth form both within an individual & between species. Correlates with greater diversity in diet their teeth also occlude (come into contact) more closely than those of reptiles. Greater surface area allows more nutrients to be extracted more rapidly two sets of teeth over lifespan. Milk teeth & adult teeth reptiles typically continually replaced teeth over lifespan. Vertical placement of limbs beneath the body (not unique to mammals) Provides better support of body & more efficient movement. Have hair (with mechano-receptive base) fine, cylindrical keratin fibres (homologous with scales & feathers) Some evidence shows that other therapsids had whiskers. Have diaphragm: dome-shaped muscle at the base of the rib cage. Helps ventilate (draw oxygen) into lungs & expel co2 increased efficiency of gas exchange.