At each end of the muscle PDF

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Anatomy and physiology...

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At each end of the muscle, the collagen fibers of the epimysium, perimysium, and endomysium, come together to form a sheath.

tendon.

ligament.

satellite cell.

tenosynovium. The dense layer of connective tissue that surrounds an entire skeletal muscle is the endomysium . fascicle. perimysium. tendon. epimysium. A fascicle is a collection of myofibrils in a muscle fiber. group of muscle fibers that are all part of the same motor unit. group of muscle fibers and motor neurons. layer of connective tissue that separates muscle from skin. group of muscle fibers that are encased in the perimysium. Muscle fibers are directly surrounded by which thin layer of connective tissue? endomysiu

m epimysium perimysium tendon The capillaries that wrap around each muscle fiber are located within the __________. perimysium epimysium sarcolemma endomysiu m What is the function of the structure indicated by the arrow?

distribute action potentials throughout the interior of the skeletal muscle cell making of energy (ATP); "power house" of the cell storage of calcium houses the genetic material (DNA) of the cell

What is the function of the structure indicated by the arrow?

making of energy (ATP); "power house" of the cell

storage of calcium

houses the genetic material (DNA) of the cell

part of coupling the action potential to contraction What is the function of the structure indicated by the arrows?

distribute action potentials throughout the interior of the skeletal muscle cell

making of energy (ATP); "power house" of the cell storage of calcium houses the genetic material (DNA) of the cell What is the function of the structure indicated by the arrow?

making of energy (ATP); "power house" of the cell distribute action potentials throughout the interior of the skeletal muscle cell storage of calcium houses the genetic material (DNA) of the cell Which of the following statements correctly describes the structure (band or line) of the sarcomere indicated by the arrow?

the region of the resting sarcomere that only contains thick filaments the point of connection for adjacent tails of the thick filaments the region of the sarcomere that contains only thin filaments the boundary between adjacent sarcomeres Interactions between actin and myosin filaments of the sarcomere are responsible for muscle contraction. muscle fatigue. the conduction of neural stimulation to the muscle fiber. the striped appearance of skeletal muscle. muscle relaxation. Which of the following best describes the term sarcomere? largely made of myosin molecules repeating unit of striated myofibrils storage site for calcium ions thin filaments are anchored here protein that accounts for elasticity of resting muscle At rest, active sites on the actin are blocked by tropomyosin molecules. ATP molecules. calcium ions. troponin molecules.

myosin molecules. The action potential is conducted into a skeletal muscle fiber by motor end plates. neuromuscular junctions. sarcoplasmic reticulum. transverse tubules. triads. The most important factor in decreasing the intracellular concentration of calcium ion after contraction is diffusion of calcium out of the cell. active transport of calcium across the sarcolemma. diffusion of calcium into the sarcoplasmic reticulum. active transport of calcium into the synaptic cleft. active transport of calcium into the sarcoplasmic reticulum. When calcium ion binds to troponin, tropomyosin rolls away from the active site. myosin shortens. active sites on the myosin are exposed. muscle relaxation occurs. actin heads will bind to myosin. Triads in skeletal muscle fibers function in __________. calcium ion uptake relaxation

calcium ion release neuromuscular transmission Identify the function of the thin filament protein at the end of the arrow.

binds to and pulls actin during a contraction binds to calcium binds to and is pulled by myosin during a contraction covers the active sites of myosin The characteristic muscle stiffness associated with rigor mortis is due to the inability of myosin filaments to detach from the active site on actin filaments. What molecule is essential for this detachment? ATP calcium acetylcholinesterase

acetylcholine Why do the disease tetanus and the normal sustained muscle contraction called tetanus share the same name? They both enable muscle fibers to reach near maximum tension. They are both brought on by bacterial infections.

They both eliminate the relaxation phase in the affected muscle fibers. All of the listed responses are correct. In response to action potentials arriving along the transverse tubules, the sarcoplasmic reticulum releases hydrogen ions. sodium ions. calcium ions. potassium ions. acetylcholine. After death, muscle fibers run out of ATP and calcium begins to leak from the sarcoplasmic reticulum into the sarcoplasm. This results in a condition known as oxygen debt. depolarization . tetany. rigor mortis. treppe. In rigor mortis sustained contractions occur. calcium ions keep binding to troponin. the myosin heads are attached to actin. ATP is depleted. All of the answers are correct. How would the loss of acetylcholinesterase from the motor end plate affect skeletal muscle?

It would produce muscle weakness. It would have little effect on skeletal muscles. It would cause muscles to stay contracted. It would make the muscles less excitable. It would cause muscles to stay relaxed. The cytoplasm of the neuromuscular terminal contains vesicles filled with molecules of the neurotransmitter epinephrine. acetylcholine. antidiuretic hormone. adrenaline. norepinephrine. Synaptic vesicles contain neurotransmitters that are released by ________ when the action potential arrives. sodium endocytosis exocytosis hydrolysis apoptosis In response to an action potential along the transverse tubules, the __________ release(s) calcium ions into the sarcoplasm. motor-end plate troponin molecules

sarcomere sarcoplasmic reticulum Which of the following situations could contribute to prolonged muscle contraction? cross-bridge formation being reduced acetylcholinesterase not being produced infrequent neural stimulus limited availability of calcium ions The muscle action potential penetrates deep into a fiber along the __________. sarcolemma sarcoplasmic reticulum transverse tubules neuromuscular junction Interactions between the thick and thin filaments are prevented by tropomyosin. To make the active sites accessible, __________ ions must bind to __________. calcium, myosin calcium, troponin sodium, troponin calcium, actin A single contraction-relaxation cycle in a muscle fiber produces a(n) motor unit. tetanic contraction.

twitch. action potential. cramp. Which of the following is important to increasing efficiency in tension production? increasing calcium reclamation increasing the latent period a shortened relaxation phase lengthening the zone of overlap A muscle producing its maximum tension for a prolonged period is in __________. rigor mortis incomplete tetanus treppe complete tetanus The increase in muscle tension that is produced by increasing the number of active motor units is called recruitment. complete tetanus. incomplete tetanus. treppe. wave summation. In which of the following would the motor units have the fewest muscle fibers? thigh muscles

postural muscles of the back muscles that control the eyes muscles of the neck calf muscles In an isotonic contraction, muscle tension exceeds the load and the muscle lifts the load. the peak tension is less than the load. tension rises and falls but the muscle length is constant. postural muscles stabilize the vertebrae. many twitches always fuse into one. Identify the incorrect statement about a single motor unit. Muscle fibers of one motor unit intermingle with the fibers of another motor unit. Fine motor skills depend on the development of small motor units. The smaller the number of muscle fibers, the more precise the movement. Some motor units include as many as 2000 muscle fibers. The more neurons involved, the more powerful the contraction. The type of contraction where the tension exceeds the load is called isotonic eccentric contraction. isotonic concentric contraction. isometric contraction. isometric concentric contraction. isometric eccentric contraction.

The type of contraction where the tension is less than the load is called isotonic eccentric contraction. isotonic concentric contraction. isometric concentric contraction. isometric contraction. isometric eccentric contraction. Which of the following allows muscles to return to their original shape during relaxation? myosin binding elastic forces gravity opposing muscle contractions gravity, opposing muscle contractions, and elastic forces What can the nervous system do to increase muscle tension? increase the number of active motor units increase stimulation frequency recruit larger motor units All of the listed responses can increase muscle tension. A resting muscle generates most of its ATP by anaerobic respiration. glycogenolysis. aerobic metabolism of fatty acids.

the tricarboxylic acid cycle. hydrolysis of creatine phosphate. Creatine phosphate is produced by the process of anaerobic respiration. cannot transfer its phosphate group to ADP. acts as an energy reserve in muscle tissue. is only formed during strenuous exercise. can replace ATP in binding to myosin molecules during contraction. During anaerobic glycolysis, pyruvic acid is produced. oxygen is not consumed. carbohydrate is metabolized. ATP is produced. All of the answers are correct. During the recovery period following exercise, all of the following are true except oxygen is consumed at above the resting rate. lactic acid is removed from muscle cells. heat is generated. the muscle actively produces ATP. muscle fibers are unable to contract. Fatigued muscles signify __________. accumulation of pyruvic acid

oxygen recovery lowered body temperature decreased pH When a skeletal muscle fiber is at rest, its ATP demands are met by __________. the breakdown of creatine phosphate aerobic metabolism of fatty acids glycolysis aerobic metabolism of glucose Which skeletal muscle fiber typeslow or fastcontains more mitochondria? (Figure 10-21) slo w fast The type of muscle fiber that is most resistant to fatigue is the ________ fiber. intermediat e fast high-density anaerobic slow Muscles that move the eyeball have ________ fibers. slow intermediate fast

circular All of the answers are correct. Increased muscle fiber endurance can be produced by __________. a muscle fiber with a smaller diameter the amount of excitation-contraction coupling the type of activity performed the length of the muscle fiber What type of muscle fibers has the longest endurance? fast slow intermediat e white The soleus muscle is very red in color. Which of these statements about soleus muscle fibers is FALSE? They have a slow twitch speed. They are slow to fatigue. They are large in diameter. They are rich in myoglobin. Cardiac muscles cells have a sarcolemma that is more permeable to calcium, which causes them to __________. have contractions that last longer than skeletal muscle fibers pump calcium back into the sarcoplasmic reticulum faster form more cross-bridges

have faster contractions than skeletal muscle fibers Smooth muscle contracts when calcium binds to __________ and activates __________. troponin; myosin light chain kinase calmodulin; actin troponin; tropomyosin calmodulin; myosin light chain kinase Joints can be classified structurally as synovial. bony. fibrous. cartilaginous. All of the answers are correct. The synarthrosis that binds the teeth to the bony sockets is a synotosis. syndesmosis. synchondrosis . suture. gomphosis. An immovable joint is a(n) synarthrosis. diarthrosis.

syndesmosis. amphiarthrosis. symphysis. A synovial joint is an example of a(n) synarthrosis. diarthrosis. syndesmosis. amphiarthrosis. symphysis. A suture is an example of a(n) symphysis. amphiarthrosis. synarthrosis. diarthrosis. syndesmosis. Dense fibrous connective tissue is to a suture as a periodontal ligament is to a(n) gomphosis. synchondrosis. synostosis. amphiarthrosis. syndesmosis. A freely movable joint is a(n)

syndesmosis. symphysis. diarthrosis. amphiarthrosis. synarthrosis. Structurally, the pubic symphysis is classified as a ________ articulation. fibrous synovial diarthrotic cartilaginou s bony What structure covers the bony surfaces of a synovial joint to prevent the surfaces from touching? (Figure 9-1) fibrous joint capsule synovial membrane meniscus articular cartilage elastic cartilage Which of the following occurs when the articular cartilage is damaged? Normal synovial joint function is unable to continue. The matrix begins to break down.

Friction in the joint increases. The exposed surface appears rough. All of the answers are correct. Which of the following is not a function of synovial fluid? protects articular cartilages shock absorption increases osmotic pressure within joint lubrication provides nutrients The surface of articular cartilage is rough. smooth. flat. slick. both slick and smooth. Mike falls off his skateboard and sprains his ankle. Which of the following most likely occurs with this type of accident? A bursa is damaged and leaks synovial fluid. A ligament is stretched and collagen fibers in the ligament are damaged. The tibia is broken and must be set in a cast. Dislocation of the ankle occurs. Articulating bones are forced out of position and ligaments are torn.

Figure 9-1 A Simplified Sectional View of the Knee Joint Use Figure 9-1 to answer the following question:

Which structure acts as a cushion and consists of fibrous cartilage?

1

2

3

4

5

Figure 9-1 A Simplified Sectional View of the Knee Joint Use Figure 9-1 to answer the following question: What type of tissue occurs at the structure labeled "3"? articular cartilage fibrocartilage bone tissue dense connective tissue synovial membrane Usually found outside the capsule, ________ protect the articular cartilages and act as packing material for the joint. fat pads menisci

bursae ligament s tendons Small pockets of synovial fluid that reduce friction and act as a shock absorber where ligaments and tendons rub against other tissues are called fasciae. fat pads. lacunae. bursae. menisci. The three functions of synovial fluid are nutrient distribution, shock absorption, and padding. stabilization. strengthening. lubrication. enzyme secretion. To pinch with a thumb and finger involves a movement called circumduction . opposition. eversion. retraction.

rotation. A twisting motion of the foot that turns the sole of the foot outward is known as dorsiflexion. plantar flexion. inversion. pronation. eversion. The movements known as dorsiflexion and plantar flexion involve moving the hip. arm. leg. hand . foot. Which of the following joints is an example of a ball-and-socket joint? shoulder elbow wrist ankle knee Which foot movement enables the ballerina to stand on her toes? plantar flexion

dorsiflexion inversion rotation eversion Lifting a stone with the tip of foot is inversion. circumduction. eversion. dorsiflexion. plantar flexion. The atlantoaxial joint is an example of a ________ joint. pivot gliding condyloid saddle ball and socket Which of the following is not a type of synovial joint? symphysi s pivot gliding hinge

condylar Within an intervertebral disc, which structure provides the tough outer layer of fibrocartilage and which structure provides the soft inner core for resiliency and shock absorption? (Figure 9-6) nucleus fibrosus; anulus pulposus anulus fibrosus; nucleus pulposus anular ligament; spinous ligament nucleus pulposus; anulus fibrosus anulus pulposus; nucleus fibrosus The gelatinous core of an intervertebral disc is called the annulus fibrosus. gelatinous pulposus. synovial fluid. nucleus pulposus. gelatinous fibrosus. The fibrocartilage outer layer of the intervertebral disc is called the synovial fluid. gelatinous pulposus. gelatinous fibrosus. nucleus pulposus. annulus fibrosus. The flava ligament is a paired ligament that connect the laminae of adjacent vertebrae.

a fibrous band that connects the posterior surfaces of adjacent vertebral bodies. a band of fibrous tissue connecting the spinous processes of adjacent vertebrae. a longitudinal fibrous band that is attached to the tips of spinous processes from C7 to the sacrum. a wide fibrous band that connect the anterior surfaces of the adjacent vertebral bodies. The ligament that provides support to the front of the knee joint is the ________ ligament. popliteal posterior cruciate tibial collateral anterior cruciate patellar The ligaments that limit the anterior-posterior movement of the tibia and maintain the alignment of the femoral and tibial condyles are the ________ ligaments. tibial collateral fibular collateral patellar cruciate popliteal In the knee joint, the medial and lateral menisci act as cushions between the articulating surfaces. are found between the patella and femur. are prominent fat pads to protect the articulating bones.

are cartilages that bind the knee to the tibia. take the place of bursae. The structures that assist the bursae in reducing friction between the patella and other tissues are the lateral menisci. medial menisci. popliteal ligaments. fat pads. cruciate ligaments. The back of the knee joint is reinforced by ________ ligaments. popliteal anterior cruciate patellar posterior cruciate tibial collateral Complete dislocation of the knee is rare because the knee is protected by the patella. the femur articulates with the tibia at the knee. the knee contains fat pads to absorb shocks. the knee contains seven major ligaments. the knee is extremely resilient. The most common athletic knee injury produces damage to the

lateral meniscus. patella. ligaments. medial meniscus. tendons. The joint that permits the greatest range of mobility of any joint in the body is the ________ joint. shoulder wrist elbow hip knee Which of the following athletes are at greatest risk of developing a rotator cuff injury? runners soccer players high jumpers tennis players baseball pitchers Which of the following explains the occurrence of a hip fracture rather than a hip dislocation? Muscles surrounding the hip joint are altogether small and thus provide little stability. Only three ligaments are present in hip joints to provide stability. Stress gets transferred from head of femur to the diaphysis via the thin neck.

There is a severe lack of capsular fibers in hip joints compared to other synovial joints. All of the above. Factors that increase the stability of the hip joint include supporting ligaments. tough capsule. almost complete bony socket. strong muscular padding. All of the answers are correct. The coxal bones articulate with the sacrum at the ________ joint. sacroiliac vertebrocoxa l vertebroilial coxosacral iliocoxal The glenoid fossa is rimmed by the fibrocartilaginous menisci glenoidum. nucleus pulposus. annulus fibrosus. fovea capitis. glenoid labrum. Nerves and blood vessels that service a muscle fiber are located in the connective tissues of its

sarcolemma. perimysium. myofibrils. sarcomere. endomysium . A weight-lifter strains to lift a heavy weight and there is no movement of the person's arms holding on to the weight. This type of contraction is called a(n) ________ contraction. tetanus isometric treppe isotonic concentri c Muscles including the term capitis would be found within or attached to the head. neck. abdomen . groin. thorax. Muscles with fibers that run parallel to the long axis of the body are called transversus. rectus.

obliquus. medialis. lateralis. Muscles with fibers that run perpendicular to the long axis of the body are called medialis. lateralis. oblique. transversus. rectus. Which muscle is ...