BIO 102 Lecture Notes - Lecture 40: Cardiac Muscle, Elastic Fiber, Middle Ear
Document Summary
How muscles and skeletons work together to provide movement. Three different types of skeletons- for structural support and mobility: Hydrostatic skeletons: skeleton has coeloms with are filled with fluid confined in a closed space. Earthworms have this skeleton, where the circular muscles and longitudinal muscles work against each other relaxing (becomes fatter and wider) or contracting (gets longer after contraction). Exoskeletons: skeleton is outside of the muscle, insects have this. Chitin: polysaccharide, hard tissue, rather than bone that makes it up. Endoskeletons: what we have, muscle covering the skeleton. Flexor muscle (biceps) contract, extensor (triceps) muscle relaxes and vice versa. Antagonistic muscles: coordinated movement of an animal"s body produced by alternating contractions of muscles with opposing actions- squeezing or pulling on its skeleton. They attach to opposite sides of the exoskeleton, across the middle of the joint. Alternating contractions move joints back and forth, allowing the animal to walk, fly, or eat.
