Lecture 2 - Vertebrate Structure & Development zool...

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Vertebrate Structure & Development zool 3405 Lecture 2 30 August 2007
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Comparative Biology and Basic Concepts What are the ‘functions’ of the shared chordate characteristics? (notochord, etc.) Just because a structure is shared does not necessarily mean that the function is also shared (temporal-distance factor?) Function and biological role are different
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Comparative Biology and Basic Concepts FUNCTION : how a structure ‘works.’ e.g ., details of how a cell makes and secretes a protein or enzyme BIOLOGICAL ROLE : what a structure or product does for an organism (how it is used) in an adaptive sense. e.g ., a protein/enzyme secreted by a pancreatic cell cleaves sugar molecules and enables the animal to use sugar in its diet
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Comparative Biology and Basic Concepts Shared chordate features, such as the notochord, can have different biological roles in different species (e.g., axial support versus developmental guidance) Message 1 : comparisons of morphological, tissue, and cellular features between or among species is complicated by differences in biological role Message 2 : how evolution works—old features can take on new biological roles (biological roles can change, function can stay the same).
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Comparative Biology and Basic Concepts Ontogeny is yet another thing that complicates comparative morphology Ontogeny is developmental history of an
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This note was uploaded on 04/13/2008 for the course ZOOL 3405 taught by Professor Phillips during the Fall '08 term at Texas Tech.

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Lecture 2 - Vertebrate Structure & Development zool...

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