Chapter 10 Muscle Tissue Flashcards Preview

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Flashcards in Chapter 10 Muscle Tissue Deck (34):
1

muscle tissue consists of cells that are highly specialized for the function of

excitability
contraction
extensibility

2

the primary functions performed by skeletal muscles are

produce skeletal movement
guard entrances and exits
maintain body temperature

3

skeletal muscles move the body by

pulling on bones of the skeleton

4

skeletal muscles are often called voluntary muscles because

they contract when stimulated by motor neurons

5

three layers of connective tissue supporting each muscle

epimysium
perimysium
endomysium

6

smallest functional unit of muscle fiber

sarcomere

7

nerves and blood vessels that supply the muscle fibers are contained within the connective tissues of the

endomysium and perimysium

8

the thin filaments consist of

a pair of protein strands wound together to form chains of actin molecules

9

the thick filaments consist of

a helical array of myosin molecules

10

all of the muscle fibers controlled by a single motor neuron constitute a

motor unit

11

the tension in a muscle fiber will vary depending on

-structure of sarcomeres
-length of muscle fibers
-number of cross-bridge interactions

12

the reason there is less precise control over leg muscle compared to the muscle of the eye is

many muscle fibers are controlled by a single motor neuron

13

the sliding filament theory explains that the physical change that takes place during contraction is

the thin filaments sliding toward center of sarcomere alongside thick filaments

14

troponin and tropomyosin are two proteins that can prevent the contractile process by

covering the active site and blocking the actin-myosin interaction

15

the first step in excitation-contraction coupling is

release of calcium ions from cisternae of sarcoplasmic reticulum

16

the amount of tension produced by an individual muscle fiber ultimately depends on

number of pivoting cross-bridges

17

skeletal muscle fibers contract most forcefully when stimulated over a

narrow range of resting lengths

18

the amount of tension produced by a skeletal muscle is controlled by

total number of muscle fibers stimulated

19

peak tension production occurs when all motor units in the muscle contract in a state of

complete tetanus

20

in an isotonic contraction...

cross-bridges must produce enough tension to overcome resistance

21

in an isometric contraction..

tension rises but length of muscle remains constant

22

a high blood concentration of the enzyme creatine phosphokinase usually indicates

serious muscle damage

23

mitochondrial activities are relatively efficient, but their rate of ATP generation is limited by

availability of oxygen

24

during the recovery period, the body's oxygen demand is

elevated above normal resting levels

25

three major types of skeletal muscle fibers in the human body

slow
intermediate
fast

26

extensive blood vessels, mitochondria, and myoglobin are found in the greatest concentration in

slow fibers

27

the length of time a muscle can continue to contract while supported by mitochondrial activities

aerobic endurance

28

altering the characteristics of muscle fibers and improving the performance of the cardiovascular system results in improving

aerobic endurance

29

the property of cardiac muscle that allows it to contract without neural stimulation

automaticity

30

the type of muscle cell that locks sarcomeres and the resulting striations

smooth

31

structurally, smooth muscle cells differ from skeletal muscle cells because smooth muscle cells..

lack myofibrils and sarcomeres

32

smooth muscle tissue differs from other muscle tissue in

excitation-contraction coupling
length-tension relationships
control of contraction

33

neural, hormonal, or chemical factors can stimulate smooth muscle contraction producing

a decrease in muscle tone

34

layers of smooth muscle in the reproductive tract of the female are important in

movement of ova
movement of sperm if present
expelling of the fetus at delivery