Chapter 10- Muscle Tissue Flashcards Preview

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Flashcards in Chapter 10- Muscle Tissue Deck (53)
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0
Q

The primary functions performed by skeletal muscles are to…

A
  1. Produce skeletal movement
  2. Guard entrances and exits
  3. Maintain body temperature
1
Q

Muscle tissue consists of cells that are highly specialized for the…

A
  1. Excitability
  2. Contraction
  3. Maintain body temperature
2
Q

Skeletal muscles move the body by…

A

Pulling on the bones of the skeleton

3
Q

Skeletal muscles are often called voluntary muscles because…

A

They contract only when stimulated by motor neurons of the central nervous system

4
Q

The three layers of connective tissue supporting each muscle are the…

A

Epimysium, perimysium, and endomysium

5
Q

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

A

Endomysium and perimysium

6
Q

The smallest functional unit of the muscle fiber is…

A

The sarcomere

7
Q

The thin filaments consist of…

A

Pair of protein strands wound together to form chains of actin molecules

8
Q

The thick filaments consist of…

A

Helical array of myosin molecules

9
Q

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

A

Thin filaments are sliding toward the center of the sarcomere alongside the thick filaments

10
Q

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

A

Covering the active site and blocking the actin-myosin interaction

11
Q

The first step in excitation-contraction coupling is the…

A

Stimulation of the sarcolemma

12
Q

Muscle relaxation begins with…

A

Breakdown of ACh by AChE

13
Q

All of the muscle fibers controlled by a single motor neuron constitute a…

A

Motor unit

14
Q

The tension in a muscle fiber will vary depending on the…

A
  1. Structure of individual sarcomeres
  2. Initial length of muscle fibers
  3. Number of cross bridge interactions within a muscle fiber
15
Q

There is less precise control over leg muscles compared to the muscles of the eye because…

A

Many muscle fibers are controlled by a single motor neuron

16
Q

Skeletal muscle fibers contract most forcefully when stimulated over a…

A

Narrow range of resting lengths

17
Q

The amount of tension produced by a skeletal muscle is controlled by…

A

The total number of muscle fibers stimulated

18
Q

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

A

Complete tetanus

19
Q

In a concentric isotonic contraction…

A

The cross bridges must produce enough tension to overcome the resistance

20
Q

In an isometric contraction…

A

Tension rises but the length of the muscle remains constant

21
Q

A high blood concentration of the enzyme creatine kinase usually indicates…

A

Serious muscle damage

22
Q

Mitochondrial activities are relatively efficient, but their rate of ATP generation is limited by the…

A

Availability of oxygen

23
Q

What has been correlated with muscle fatigue?

A

A decline of pH within the muscle, altering enzyme activities

24
Q

During the recovery period, the body’s oxygen demand is…

A

Elevated above normal resting levels

25
Q

The three major types of skeletal muscle fibers in the human body are…

A

Slow, intermediate, fast

26
Q

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

A

Slow fibers

27
Q

The length of time a muscle can continue to contract while supported by mitochondrial activities is referred to as…

A

Aerobic endurance

28
Q

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

A

Aerobic endurance

29
Q

The property of cardiac muscle that allows it to contract without neural stimulation is…

A

Automaticity

30
Q

Structurally, smooth muscle cells differ from skeletal muscle cells because smooth muscle cells…

A

Lack myofibrils and sarcomeres

31
Q

Smooth muscle tissue differs from other muscle tissue in…

A
  1. Excitation-contraction coupling
  2. Length-tension relationships
  3. Control of contraction
32
Q

Neural, hormonal, or chemicals factors can stimulate smooth muscle contraction, producing…

A

A decrease in muscle tone

33
Q

Muscle contraction occurs as a result of…

A

Interactions between the thick and thin filaments of ten sarcomeres

34
Q

The area of the A band in the sarcomere consists of…

A

M line, H band, and zone of overlap

35
Q

The process of cross bridging, which occurs at an active site, involves a series of sequential cyclic reactions that include…

A

Attach, pivot, detach, and return

36
Q

Excitation-contraction coupling forms the link between…

A

Electrical activity in the sarcolemma and the initiation of a contraction

37
Q

When Ca2+ binds to troponin, it produces a change by…

A

Exposing the active site on the thin filaments

38
Q

The phase of a single twitch in sequential order are…

A

Latent period, contraction phase, relaxation phase

39
Q

After contraction, a muscle fiber returns to its original length through…

A

Elastic forces and the movement of opposing muscles

40
Q

A muscle producing almost peak tension during rapid cycles of contraction and relaxation is said to be in…

A

Incomplete tetanus

41
Q

The process of reaching complete tetanus is obtained by…

A

Increasing the rate of stimulation until the relaxation phase is completely eliminated

42
Q

The total force exerted by a muscle as a whole depends on…

A
  1. The rate of stimulation
  2. How many motor units are activated
  3. The number of calcium ions released
43
Q

The principal energy reserves found in skeletal muscle cells are…

A

ATP, creatine phosphate, and glycogen

44
Q

The two mechanisms used to generate ATP from glucose are…

A

Carbohydrates, fats, and proteins

45
Q

In anaerobic glycolysis, glucose is broken down to pyruvic acid, which is converted to…

A

Lactic acid

46
Q

The maintenance of normal body temperature is dependent upon…

A

The production of heat by muscles

47
Q

Growth hormone from the pituitary gland and the male sex hormone, testosterone, stimulate…

A

Synthesis of contractile proteins and the enlargement of skeletal muscles

48
Q

The hormone responsible for stimulating muscle metabolism and increasing the force of contraction during a sudden crisis is…

A

Epinephrine

49
Q

The type of skeletal muscle fibers that have low fatigue resistance are…

A

Fast fibers

50
Q

An example of an activity that requires anaerobic endurance is…

A

A 50 yard dash

51
Q

Athletes training to develop anaerobic endurance perform…

A

Frequent, brief, intensive workouts

52
Q

The major support that the muscular system gets from the cardiovascular system is…

A

Nutrient and oxygen delivery and carbon dioxide removal