Muscle Skeletal Muscle

NAME LAB TIME/ involvement _ Microscopic Anatomy and Organization of hard up Muscle Skeletal Muscle Cells and Their packaging into Muscles1. Use the items in the key to flop light upon the structures described below. g perimysium c fascicle Key a. b. c. endomysium epimysium fascicle role myofibril myo fibril perimysium sarcolemma sarcomere sarcoplasm brawn 1. 2. 3. 4. 5. 6. 7. link weave ensheathing a tamp down of heft stalls roll of brawniness cells contractile unit of pass sarcomere d fiber a endomysium h sarcolemma e myofibril d. a bodybuilder cell thin reticular connective interweave surrounding each heft cell plasma tissue layer of the muscular tissue fiber a long filamentlike organelle with a banded carriage found within vigour cells actin- or myosin-containing structure e. f. g. h. 1. f myofilament 8. 9. j. k. k tendon stack of collagen fibers that attaches a brawn to a bone2. List three reasons wherefore the connective tissue wrappings of skeletal mu scle be important.The connective tissue wrappings (a) bundle the muscle fibers together, increasing coordination of their activity (b) work strength to the muscle and (c) provide a route for entry and exit of line of business vessels and nerves to the muscle fibers.3. Why be there more indirect-that is, tendinous-muscle attachments to bone than there are direct attachments? They conserve quadriceps femoris (less bulky than fleshy muscle attachments) and are more durable than muscle tissue where bony prominences must be spanned.4. How does an aponeurosis disagree from a tendon structurally? tendon is a band or cord of the same tissue. An aponeurosis is a sheet of white-hot fibrous connective tissue The diagram illustrates a small portion of some(prenominal) myofibrils. Using letters from the key, correctly identify each structure indicated by a leader line or a bracket. Key a. b. c. A band actin filament I band d. e. f. myosin filament T tubule terminal cisterna g. h. i. triad sarcomere Z disc . On the following figure, strike out a blood vessel, endomysium, epimysium, a fascicle, a muscle cell, perimysium, and the tendon. Perimysium Tendon Epimysium Fascicle 90 Review Sheet 14 r. The neuromuscular Junction7. Complete the following statements The alignment amidst a tug neurons axon and the muscle cell membrane is called a neurornuseular junction or a _1_ junction. A motor neuron and all of the skeletal muscle cells it stimulates is called a _2_. The actual gap surrounded by the axon terminal and the muscle cell is called a _3_.Within the axon terminal are many small vesicles containing a neurotransmitter center called_4_. When the _5_ reaches the ends of the axon, the neurotransmitter is released and diffuses to the muscle cell membrane to concur with receptors there. The combining of the neurotransmitter with the muscle membrane receptors causes the membrane to become permeable to both atomic number 11 and potassium. The greater influx of sodium ions results in _6_ of the membrane. Then contraction of the muscle cell drop deads. 1. 2. 3. 4. 5. 6. yoneural motor unit synaptic whirl acetylcholine nerve impulse (action potential) depolarization 8. The events that occur at a neuromuscular junction are depicted below. Identify by labeling every structure provided with a leader line. Key a. b. a e c. d. e. gist axon terminal mitochondrion muscle fiber myelinated axon sarcolemma synaptic cleft synaptic vesicle T tubule f. c g. h. (a) g-, b f, JunctionalR folds of the sarcolemma h -+. r- -I Part of a myofibril (b) Review Sheet 14 91