BIO 1306 Lecture Notes - Lecture 7: Ecdysis, Ecdysozoa, Eumetazoa
Document Summary
Most animals are mobile and use traits such as strength, speed, toxins, or camouflage to detect, capture, and eat other organisms. For example, the chameleon captures insect prey with its long, sticky, quick-moving tongue. Concept 32. 1: animals are multicellular, heterotrophic eukaryotes with tissues that develop from embryonic layers. There are exceptions to nearly every criterion for distinguishing animals from other life-forms. Several characteristics, taken together, sufficiently define the group. Their bodies are held together by structural proteins such as collagen. Nervous tissue and muscle tissue are unique, defining characteristics of animals. Tissues are groups of similar cells that act as a functional unit. Video: sea urchin embryonic development (time lapse) Most animals have at least one larval stage. A larva is sexually immature and morphologically distinct from the adult; it eventually undergoes metamorphosis to become a juvenile. A juvenile resembles an adult, but is not yet sexually mature.
