BIOL 111 Lecture Notes - Lecture 10: Filter Feeder, Motility, Choanoflagellate

• School: McGill University
• Department: Biology (Sci)
• Course: BIOL 111
• Professor: Rajinder Dhindsa

Document Summary

Biol 111-lecture 10-introduction to animals sponges: characteristics of animals, eukaryotic, heterotrophic. -most have internal digestion internal gut that is continuous with the outside environment and permits internal digestion (compare to fungi, external digestion) -organism can grow in size *constraint on growth cell surface area/volume ratio: multicellularity, no cell walls. -hydrostatic skeleton muscles contract against fluid-filled cavity e. g. earthworms. -exoskeleton (external) non-living covering that does not grow with animal. --non-living in invertebrates (e. g. caco3: motile at some life stage. -reduces competition, enhances genetic diversity: somatic (body) cells are diploid (2n, *most animals have tissues. -groups of similar cells organized into a functional unit. -can function together as organs to complete more complex tasks: position of animals on the tree of life, closest to ancestral animals colonial choanoflagellate protists, first appear in late pre-cambrian, diverse in cambrian explosion, monophyletic similar gene sequences.