Anatomy and Function of Muscles: Types, Composition, and Contraction, Quizzes of Biology

Download Anatomy and Function of Muscles: Types, Composition, and Contraction and more Quizzes Biology in PDF only on Docsity! TERM 1 What are Muscles good for? DEFINITION 1 1. Movement 2. Stabilization 3. Posture 4. Generating Heat a. When you "shiver ". Your muscles are shaking to warm up the body TERM 2 Skeletal Muscle DEFINITION 2 Voluntary Striated Muscle that you can consciously control the movement of. Found in all limbs and body walls. TERM 3 Cardiac Muscles DEFINITION 3 Cardiac muscle is a type of involuntary striated muscle found in the walls and histologic foundation of the heart, specifically the. - Also innervated by the Autonomic Nervous System -Incapable of division + have no satellite cells so no regeneratin after injury. - Branch and rejoin each other the union facilitated by an intercalated disc. TERM 4 Smooth Muscle DEFINITION 4 Smooth muscle is an involuntary non-striated muscle. - Innervated by the A.N.S - Found in the walls of blood vessels and hollow internal organs -Will contract in response to stretch of lumen it surrounds. -slower to contract than skeletal muscle but stays contracted much longer. TERM 5 Fascia DEFINITION 5 A fascia is a layer of fibrous tissue that permeates the human body. -Fibrous CT (primary collagen fibers) -Surrounds and separates muscles in the body TERM 6 Tendon DEFINITION 6 A cord-like fascial extension at the end of the muscle attaching it to the body by the intermingling of collagen fibers with those of the periosteum. TERM 7 Aponeurosis DEFINITION 7 Aponeuroses are layers of flat broad tendons of fascia attaching muscle to muscle or bone. TERM 8 Sharpey's Fibers DEFINITION 8 Sharpey's fibers are a matrix of connective tissue consisting of bundles of strong collagenous fibers connecting periosteum to blend with the collagen fibers of tendons. Which forms a contractile unit. TERM 9 Skeletal Muscle (Make-up) DEFINITION 9 -Parallel striated muscle cells (fibers) -Contract in response to acetylcholine -Striated appearance comes from the arrangement of various myofilaments found within the contractile units (sarcomeres) of the muscle TERM 10 Sarcomere DEFINITION 10 The smallest functional unit of a skeletal muscle cell. - extends from z-line to z-line. TERM 21 Perimysium DEFINITION 21 -Surrounds bundles of fibers of fascicles -Pathway for blood vessels into muscle tissue. TERM 22 Endomysium DEFINITION 22 -Delicate, Loose CT, investing each muscle fiber (cell) TERM 23 What controls contraction DEFINITION 23 -Each muscle contract witha nerve ending at the neuromuscular junction(synapse) between the nerve ending and the muscle cell. -Eye muscle: 1 nerve, 3 muscle cells - back muscle: 1 neuron, 100's of muscle cells TERM 24 Intercalated disks DEFINITION 24 -specialized junctional connections between adjacent cardiocytes. - Composed of two main structures: - Desmosomes -- into which the myofibrils anchor forming a bridge between cells so all cells pull together when their sarcomeres contract. -Gap Junctions -- allow ions and molecules to move between cells providing communication between cells. -Occur at the Z-lines of the cardiac muscle sarcomere. TERM 25 Smooth Muscle Arrangement DEFINITION 25 2 arrangements: -Multiunit: -muscle fibers poorly org. - function as individual fibers not together as a syncytium -In walls of b.v's and the iris of the eye. -Contract in response to nerves impulses & hormones TERM 26 Smooth Muscle Arrangement II DEFINITION 26 -Visceral (single-unit) -Sheets of spindle shaped cells held together via gap junctions -found in walls of hollow organs ex. -- stomach, intestines, bladder, uterus -arranged in 2 thick layers. -outer longitudinally directed fibers -Inner circularly directed fibers -fibers are able to stimulate ea. other in contract TERM 27 Smooth Muscle Cells DEFINITION 27 -are small, can exhibit gap junctions -have no t-tubules - exhibit poorly developed sarcoplasmic reticulum -are spindle- shaped with tapered ends -the single central nucleus can divide - therefore regeneration after injury possible or also hyperplasia (increase in cell number) -actin & myosin randomly arranged therefore no striations TERM 28 Location of Smooth Muscle DEFINITION 28 -In walls of all blood vessels (except heart) -In walls of hollow organs i.e. urinary bladder -In organized layers in the walls of the respiratory, circulatory, digestive, and reproductive tracts TERM 29 Rhythmaticity DEFINITION 29 Displayed by smooth muscle cells -Pattern of repeated contractions -results from self exciting fibers which spreads to adjacent cells Ex. Peristalsis -- slow contractile waves of the gastrointestinal tract that results from fibers stimulating each other - alternate contractions and relaxations of smooth m. around tubular organs. While typical peristalsis moves food from the oral cavity down the esophagus to the stomach, reverse peristalsis is vomiting.