Muscular System Overview

muscles

the organ system that enables the body to have flexibility and movement.

skeletal muscle, smooth muscle, cardiac muscle

<p>A muscle that is attached to the bones of the skeleton and provides the force that moves the bones.</p> Signup and view all the answers

<p>Involuntary muscle found inside many internal organs of the body.</p> Signup and view all the answers

<p>Found only in the heart, involuntary control, contracts to propel blood into the circulatory system.</p> Signup and view all the answers

<p>A fibrous membrane covering, supporting and separating muscles.</p> Signup and view all the answers

<p>Attaches muscle to bone.</p> Signup and view all the answers

<p>Connective tissue that forms broad fibrous sheets which may attach to the covering of adjacent muscles.</p> Signup and view all the answers

<p>Connective tissue that closely surrounds a skeletal muscle.</p> Signup and view all the answers

<p>Layer of connective tissue that extends inward from the epimysium &amp; separates the muscle tissue into small sections.</p> Signup and view all the answers

<p>Bundles of skeletal muscle fibers.</p> Signup and view all the answers

<p>Connective tissue surrounding a muscle fiber.</p> Signup and view all the answers

<p>Fibrous covering that surrounds deeper organs, even epimysium of muscles.</p> Signup and view all the answers

<p>Layer of tissue that is under the skin and connects the skin to muscles and underlying tissues.</p> Signup and view all the answers

<p>Bundles of protein filaments within the muscle fiber.</p> Signup and view all the answers

<p>A protein that makes up nearly half of the proteins in muscle cells.</p> Signup and view all the answers

<p>A contractile protein that is part of the thin filaments in muscle fibers.</p> Signup and view all the answers

<p>Striations that form a repeating pattern of units along each muscle fiber.</p> Signup and view all the answers

<p>Organelle of the muscle fiber that stores calcium.</p> Signup and view all the answers

<p>System of tubules that provides channels for ion flow throughout the muscle fibers to facilitate the propagation of an action potential.</p> Signup and view all the answers

<p>Overstretching, overexertion, or overuse of soft tissue, less severe than a sprain.</p> Signup and view all the answers

<p>Because muscle cells only contract not extend; skeletal muscles work in pairs.</p> Signup and view all the answers

<p>A junction where information is transmitted from one neuron to the next.</p> Signup and view all the answers

<p>Chemical messengers that cross the synaptic gaps between neurons.</p> Signup and view all the answers

<p>Neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.</p> Signup and view all the answers

<p>Region where a motor neuron comes into close contact with a skeletal muscle cell.</p> Signup and view all the answers

<p>A small gap that separates the membrane of the neuron &amp; the membrane of the muscle fiber.</p> Signup and view all the answers

<p>A neurotransmitter that enables learning and memory and also triggers muscle contraction.</p> Signup and view all the answers

<p>A fixed muscular contraction after death.</p> Signup and view all the answers

<p>Inflammation of a tendon.</p> Signup and view all the answers

<p>Inflammation of the sheath surrounding a tendon.</p> Signup and view all the answers

<p>Acute, contagious viral disease of the central nervous system that can lead to paralysis.</p> Signup and view all the answers

<p>A human genetic disease caused by a sex-linked recessive allele; characterized by progressive weakening and a loss of muscle tissue.</p> Signup and view all the answers

<p>sarcomere</p> Signup and view all the answers

<p>ATP.</p> Signup and view all the answers

<p>Rare poisoning caused by toxins produced by Clostridium botulinum bacteria.</p> Signup and view all the answers

<p>A chart of the timing and strength of a muscle's contraction.</p> Signup and view all the answers

<p>A muscle fiber or cell and motor neuron that connects to it.</p> Signup and view all the answers

<p>A disease in which acetylcholine receptors on muscle cells are destroyed so that muscles can no longer respond to the acetylcholine signal to contract.</p> Signup and view all the answers

<p>Step 1: A nerve impulse travels down an axon and causes the release of acetylcholine. Step 2: Acetylcholine causes the impulse to spread across the surface of the sarcolemma. Step 3: The nerve impulse enters the T Tubules and Sarcoplasmic Reticulum, stimulating the release of calcium ions. Step 4: Calcium ions combine with Troponin, shifting troponin and exposing the myosin binding sites on the actin. Step 5: ATP breaks down ADP + P. The released energy activates the myosin cross bridges and results in the sliding of thin actin myofilament past the thick myosin myofilaments. Step 6: The sliding of the myofilaments draws the Z lines towards each other, the sarcomere shortens, the muscle fibers contract and therefore muscle contracts. Step 7: ACh is inactivated by Acetylcholinesterase, inhibiting the nerve impulse conduction across the sarcolemma. Step 8: Nerve impulse is inhibited, calcium ions are actively transported back into the Sarcoplasmic Reticulum, using the energy from the earlier ATP breakdown. Step 9: The low calcium concentration causes the myosin cross bridges to separate from the thick actin myofilaments and the actin myofilaments return to their relaxed position. Step 10: Sarcomeres return to their resting lengths, muscle fibers relax and the muscle relaxes.</p> Signup and view all the answers

<ol> <li>ACh rapidly decomposes the remaining ACh in the synapse. 2. Muscle impulses stop. 3. Stimulus to sarcolemma &amp; muscle fiber membrane ceases. 4. Calcium moves back into sarcoplasmic reticulum (SR). 5. Myosin &amp; actin binding prevented. 6. Muscle fiber relaxes.</li> </ol> Signup and view all the answers

<ol> <li>Myosin head attaches to actin binding sites, forming cross-bridges. 2. Myosin cross-bridge pulls thin filament. 3. ADP &amp; phosphate released from myosin. 4. New ATP binds to myosin. 5. Linkage between actin &amp; myosin cross-bridge breaks. 6. ATP splits. 7. Myosin cross-bridge goes back to original position.</li> </ol> Signup and view all the answers

<p>An energy storage molecule used by muscle tissue; can be removed and attached to an ADP to generate ATP quickly.</p> Signup and view all the answers

<p>heat</p> Signup and view all the answers

<p>The amount of oxygen required after physical exercise to convert accumulated lactic acid to glucose.</p> Signup and view all the answers

<p>Composed of myosin protein; forms cross bridges.</p> Signup and view all the answers

<p>Composed of actin protein; associated with troponin &amp; tropomyosin proteins.</p> Signup and view all the answers

<p>Oxygen-storing pigment in muscle tissue.</p> Signup and view all the answers

<p>The value of exercise intensity at which lactic acid production increases.</p> Signup and view all the answers

<p>Stimulation level that must be reached to elicit an action potential in a neuron or muscle fiber.</p> Signup and view all the answers

<p>Inability of a muscle to maintain its strength of contraction or tension.</p> Signup and view all the answers

<p>A painful and involuntary muscle contraction.</p> Signup and view all the answers

<p>Period of time during which the neuron cannot generate another action potential.</p> Signup and view all the answers

<p>When a muscle fiber responds completely or not at all to a stimulus.</p> Signup and view all the answers

<p>A single quick, jerky muscular contraction from a single nerve impulse followed by relaxation.</p> Signup and view all the answers

<p>Normal state of balanced muscle tension.</p> Signup and view all the answers

<p>Increase force of contraction by a skeletal muscle fiber when a twitch occurs before the previous twitch relaxes.</p> Signup and view all the answers

<p>A sustained contraction that lacks partial relaxation.</p> Signup and view all the answers

<p>An increase in the number of motor units being activated.</p> Signup and view all the answers

<p>When skeletal muscles develop tension and shorten when an external force is applied.</p> Signup and view all the answers

<p>Lengthening of the muscle.</p> Signup and view all the answers

<p>When a skeletal muscle develops tension but does not shorten.</p> Signup and view all the answers

<p>Dark muscle fibers for long sustained or continued contractions.</p> Signup and view all the answers

<p>Fibers characterized as inefficient and fatiguable with low aerobic power.</p> Signup and view all the answers

<p>White, fast twitch, rapid contraction fibers.</p> Signup and view all the answers

<p>A smooth muscle tissue that forms sheets or layers in the walls of visceral organs.</p> Signup and view all the answers

<p>Spontaneous repeated contractions.</p> Signup and view all the answers

<p>Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.</p> Signup and view all the answers

<p>Multiunit smooth muscle and visceral smooth muscle.</p> Signup and view all the answers

<p>Muscle fibers that are less well organized and function as separate units.</p> Signup and view all the answers

<p>via intercalated disks (gap junctions)</p> Signup and view all the answers

<p>To protect the brain and spinal cord from trauma and provide a fluid for diffusion.</p> Signup and view all the answers

<p>Less movable end of a muscle.</p> Signup and view all the answers

<p>More movable end of a muscle.</p> Signup and view all the answers

<p>A muscle that causes an action.</p> Signup and view all the answers

<p>A muscle functioning in cooperation with another muscle.</p> Signup and view all the answers

<p>Muscle responsible for a particular body movement.</p> Signup and view all the answers

<p>Chemicals that block the action of a particular neurotransmitter.</p> Signup and view all the answers

<p>Lack troponin; use calmodulin to bind calcium; slower to contract &amp; relax.</p> Signup and view all the answers

<p>Only in the heart, composed of striated cells, forming fibers that are interconnected.</p> Signup and view all the answers

<p>Generate a great variety of body movements; bones and muscles act as levers.</p> Signup and view all the answers

<ol> <li>rigid bar 2. fulcrum 3. resistance 4. force</li> </ol> Signup and view all the answers

<p>Parts are arranged 1. resistance 2. fulcrum 3. force</p> Signup and view all the answers

<p>Seesaws &amp; scissors.</p> Signup and view all the answers

<p>Parts are arranged 1. fulcrum 2. resistance 3. force</p> Signup and view all the answers

<p>Wheelbarrow.</p> Signup and view all the answers

<p>Parts are arranged 1. resistance 2. force 3. fulcrum</p> Signup and view all the answers

<p>Tweezers.</p> Signup and view all the answers

<p>A muscle of large size in the pectoral region.</p> Signup and view all the answers

<p>Shaped like a delta or triangle.</p> Signup and view all the answers

<p>Extends digits (fingers).</p> Signup and view all the answers

<p>Extends digits (toes).</p> Signup and view all the answers

<p>A muscle with two heads in the brachium (arm).</p> Signup and view all the answers

<p>Attached to the sternum, clavicle, &amp; mastoid process.</p> Signup and view all the answers

<p>Located near the outside, with fibers that run obliquely.</p> Signup and view all the answers

<p>Covers the upper part of the cranium &amp; consists of two muscular parts: the frontalis &amp; occipitalis.</p> Signup and view all the answers

<p>A ring-like band of muscle that surrounds the eye.</p> Signup and view all the answers

<p>A sphincter muscle that encircles the mouth.</p> Signup and view all the answers

<p>Located in the wall of the cheek on the outer surface of maxilla and mandible.</p> Signup and view all the answers