front 1 Excitability | back 1 the ability to respond to stimulus |
front 2 Conductivity | back 2 electrical changes that travels along the plasma membrane opening voltage-gated channels |
front 3 Contractility | back 3 contractile proteins within in the muscle slide past one another (sliding |
front 4 Elasticity | back 4 ability to return to its original length |
front 5 Extensibility | back 5 Lengthening of a muscle fiber |
front 6 skeletal Muscle Functions | back 6 -Body Movement -Maintenance of posture |
front 7 Muscle Fiber | back 7 muscle cell |
front 8 Fascicle | back 8 group of |
front 9 Myofibril | back 9 small tubules with in the muscle fiber that contain the contractile
unit called |
front 10 Connective Tissue Functions | back 10 -Protection -Sites for distribution of blood vessels and nerves -Attachment to the skeleton |
front 11 3 Layers of Connective Tissue | back 11 -Epimysium -Perimysium -Endomysium |
front 12 Epimysium | back 12 -Surrounds the whole muscle -Dense irregular tissue |
front 13 Perimysium | back 13 -Surrounds the fascicle -Dense irregular tissue -Contains lots of blood vessels and nerves |
front 14 Endomysium | back 14 -Surrounds and electrically insulates each individual muscle fiber -Areolar tissue -Contains reticular fibers to help bind together muscle fibers |
front 15 Tendon | back 15 -Thick cord like structure -Formed by three layers of connective tissue -Dense irregular tissue -Attach muscle to bone |
front 16 Aponeurosis | back 16 -A thin flattened sheet of dense irregular tissue -Connects two muscle bellies |
front 17 Muscle Fiber Structure | back 17 -Multi nucleated -Special cell membrane -Sarcoplasmic reticulum -Myofibrils -Myofilaments -Sarcomere |
front 18 Multinucleated | back 18 Myoblasts fuse to form a single muscle fiber |
front 19 Satellite Cells | back 19 Myoblasts that do not fuse -Remain in muscle tissue to repair damaged muscle tissue |
front 20 Sarcolemma | back 20 Conducts electrical impulses |
front 21 T-tubules | back 21 deep invaginations of the sarcolemma that extend into the skeletal muscle fiber to stimulate the sarcoplasmic reticulum |
front 22 Sarcoplasmic Reticulum (SER) | back 22 Internal membrane complex that is similar to smooth ER |
front 23 Terminal Cisternae | back 23 Sacs at the end of the SER that store calcium |
front 24 Calcium pumps vs calcium channels | back 24 Pumps: Move calcium into SER Channel: Move calcium out of SER |
front 25 Calcmodulin and Calsquestrin | back 25 Proteins that bind calcium with the SER |
front 26 Myofibrils | back 26 -Long, cylindrical structures that extend the length of the muscle fiber -80% of the skeletal muscle volume -Composed of the myofilaments |
front 27 Myofilaments | back 27 -Contractile proteins that are bundled within the myofibrils |
front 28 2 Types of Myofilaments | back 28 Myosin=thick Actin=thin |
front 29 Thick | back 29 -200 to 500 myosin proteins -Myosin: globular head and elongated tail (golf club) |
front 30 Thin | back 30 -Composed of 2 strands of actin protein -Actin: 2 protein strands that are twisted around each other |
front 31 Tropomyosin | back 31 regulatory protein that covers the myosin binding sites of actin until |
front 32 Troponin | back 32 regulatory protein that binds with calcium to move tropomyosin off of the myosin binding sites of actin |
front 33 Sarcomere | back 33 -Repeating units within the myofilaments -The contractile unit |
front 34 Z Disc | back 34 proteins that are positioned perpendicular to the myofilaments and serve as anchors for the thin filaments -separates sarcomeres |
front 35 I Bands | back 35 extend in both directions of a Z disc -thin filaments only -disappears during maximal contraction |
front 36 A Band | back 36 central region that contains the entire -thin overlaps thick slightly -does not change shape during contraction |
front 37 H Zone | back 37 most central portion of the A band -NO thin filament over lapping! Thick filaments only! -disappears as well |
front 38 M Line | back 38 thin transverse protein meshwork in the center of the H zone -attachment for thick filaments |
front 39 Connection (green coil on diagram) | back 39 extends from the Z disc to the M line through the core of each thick filament -stabilizes thick filaments -has coiled section to help with recoil; able to return to normal shape after contraction |
front 40 Dystrophin | back 40 a complex protein that anchors myofibrils to other proteins with in
the |
front 41 GO OVER MUSCLE CONTRACTION STEPS!!! | back 41 Find them in slides on #33 and after that. |
front 42 Skeletal Muscle Fiber Types | back 42 -Fast-twitch -Slow-twitch -Fast Glycolytic |
front 43 Fast-twitch | back 43 -Anaerobic -Larger in diameter -Strength and speed -Light in color -Contains medium amounts of mitochondria and myoglbin |
front 44 Slow-twitch | back 44 -Aerobic -Small in diameter -appear red -contain lots of mitochondria and myoglobin -endurance |
front 45 Fast Glycolytic (anaerobic fibers) | back 45 -anaerobic -largest fibers -white in color -contains few mitochondria or myoglobin -short duration (sprinting and weight lifting) |
front 46 Factors affecting tension | back 46 -length-tension relationship -length-tension curve |
front 47 Length-tension relationship | back 47 the amount of overlap of thick and thin filaments when the muscle begins its contraction |
front 48 length-tension curve | back 48 muscle generates different amounts of tension dependent upon its length at the time of stimulation |
front 49 Muscle Tension | back 49 resting tension in a muscle generated by involuntary nervous stimulation of the muscle |
front 50 Muscle Fatigue | back 50 The reduced ability to inability of the muscle to produce muscle tension |
front 51 Isometric contraction | back 51 contraction of a muscle where no movement is created |
front 52 Isotonic contraction | back 52 muscle tension results in movement of the muscle |
front 53 Concentric contraction | back 53 shortening of the muscle length (Occurs when the muscle tension is greater than resistance) |
front 54 Eccentric contraction | back 54 lengthening of the muscle (Muscle exerts less force than needed to move the load) |
front 55 Cardiac Muscle Cells | back 55 -Short -Y branching -1 or 2 nuclei -striated -joined by intercalated disc |
front 56 Autorhythmic | back 56 Specialized muscle cells that are |
front 57 Compare smooth vs skeletal muscle SMOOTH | back 57 -Thick filaments have myosin heads along entire length -Myosin heads have a modification to latch-on to thin filament (latchbridging) -NO troponin, instead has MLCK (myosin light-chain kinase) and myosin light chain phophatase |
front 58 Compare smooth vs skeletal muscle SKELETAL | back 58 -Thick filaments have myosin heads along the ends -No latchbridging -Has troponin |
front 59 Compare smooth vs skeletal muscle BOTH | back 59 -Calcium stimulates contraction -Myosin uses ATP for power stroke -Thin filament slides |