BIOL 111 Lecture 6: Lecture 6 Intro to Animals

• School: McGill University
• Department: Biology
• Course: BIOL 111
• Professor: Andrew Hendry

Document Summary

On the tree of life animals are pretty insignificant. Animal characteristics: eukaryotic, true nucleus , complex organelles, compartmentalized in cytoplasm, heterotrophic, different feeding , use preformed organic molecules for energy, carbon based, animals can be. 3x3x3 cube sa 54, v 27, 4x4x4 sa 96, v 64: the membrane is the only way to take in nutrients and expel waste. The amount a cell can take in is limited: due to multicellularity, animals have specialized tissues, connective, adipose, reticular, muscular. Epithelial: nervous, tissues make up specialized organs with complex functions. Projections, and folds like villi increase surface area: no cell walls, cell lacks structure, requires skeleton, hydrostatic skeleton -muscles contract against fluid filled body cavity, present in soft bodied animals, like octopodes, earthworms. Exoskeleton -shell: limits growth of organism, but protects it from predation, does not grow with organism, support for mechanic movement, present in arthropods, ecdysozoans, molting animals. Derived from universal common ancestor, diversification is late by comparison.