Muscles

Question 1

This muscle tissue is striated: Alternating light and dark bands as seen when examined with a microscope

Answer 1

skeletal & cardiac muscle

Question 2

What kind of muscle moves bones

Answer 2

skeletal

Question 3

What kind of muscle is contrasted autorhythmicly and initiated by a node of tissue called the “pacemaker”

Answer 3

cardiac

Question 4

Located in the walls of hollow internal structures Ie: Blood vessels, airways, and many organs

Answer 4

smooth muscle tissue

Question 5

Which kind of muscle is voluntary

Answer 5

skeletal

Question 6

Which kind of muscle is involuntary

Answer 6

cardiac & smooth

Question 7

List the functions of Muscles

Answer 7

• body movement
• stabilizing body positions
• moving substances within the body
• generating heat

Question 8

What are the properties that enable muscle to function and contribute to homeostasis

Answer 8

• electrical excitability
• contractility
• extensibility
• elasticity

Question 9

Dense sheet or broad band of irregular connective tissue that surrounds muscles

Answer 9

fascia

Question 10

Epimysium

Answer 10

The outermost layer Separates 10–100 muscle fibers into bundles called fascicles

Question 11

Surrounds numerous bundles of fascicles

Answer 11

Perimysium

Question 12

Separates individual muscle fibers from one another

Answer 12

Endomysium

Question 13

Cord that attach a muscle to a bone

Answer 13

Tendon

Question 14

Aponeurosis

Answer 14

Broad, flattened tendon

Question 15

Sarcolemma

Answer 15

The plasma membrane of a muscle cell

Question 16

Transverse (T) tubules

Answer 16

Connect the plasma membrane to the interior of the cell

Muscle action potentials travel through the T tubules Ensure that action potential excites all parts of the muscle fiber at the same time

Question 17

Sarcoplasm

Answer 17

the cytoplasm of a muscle fiber

Question 18

Sarcoplasm includes glycogen used for synthesis of ATP and a red-colored protein called _________ which binds oxygen molecules

Answer 18

myoglobin

Question 19

Myoglobin releases __________ when it is needed for ATP production

Answer 19

oxygen

Question 20

Neurons that stimulate skeletal muscle to contract are _____________________

Answer 20

somatic motor neurons

Question 21

Muscle growth occurs by what

Answer 21

hypertrophy

An enlargement of existing muscle fibers

Question 22

_____________ retain the capacity to regenerate damaged muscle fibers

Answer 22

Satellite cells

Question 23

Myofibrils

Answer 23

Thread-like structures which have a contractile function

Question 24

Sarcoplasmic reticulum

Answer 24

Membranous sacs which encircles each myofibril

• Stores calcium ions (Ca2+)
• Release of Ca2+ triggers muscle contraction

Question 25

Filaments

Answer 25

* Function in the contractile process * Two types of filaments (Thick and Thin) * There are two thin filaments for every thick filament

Question 26

Sarcomeres

Answer 26

Compartments of arranged filaments Basic functional unit of a myofibril

Question 27

Z discs

Answer 27

Separate one sarcomere from the next Thick and thin filaments overlap one another

Question 28

A band

Answer 28

Darker middle part of the sarcomere

Question 29

I band

Answer 29

Lighter, contains thin filaments but no thick filaments Z discs pass through the center of each I band

Question 30

H zone

Answer 30

Center of each A band which contains thick but no thin filaments

Question 31

M line

Answer 31

Supporting proteins that hold the thick filaments together in the H zone

Question 32

The Sliding Filament Mechanism: ___________ attach to and “walk” along the thin filaments at both ends of a sarcomere

Answer 32

Myosin heads

Question 33

When the muscle contracts __________ come closer together and the sarcomere shortens

Answer 33

Z discs

Question 34

Which are the three ways in which muscle fibers have ways to produce ATP

Answer 34

1. Creatine phosphate 2. anaerobic cellular respiration 3. aerobic cellular respiration

Question 35

what are some of the factors which contribute to muscle fatigue

Answer 35

* Inadequate release of calcium ions from the SR * Depletion of creatine phosphate * Insufficient oxygen * Depletion of glycogen and other nutrients * Buildup of lactic acid and ADP * Failure of the motor neuron to release enough acetylcholine

Question 36

oxygen consumption after exercise: the added oxygen is used to restore muscle to the resting level in three ways, list them

Answer 36

1. Converts lactic acid into glycogen 2. Synthesizes creatine phosphate and ATP 3. Replaces the oxygen removed from myoglobin

Question 37

control of muscle tension: What is the maximum tension (force) is dependent on

Answer 37

* The rate at which nerve impulses arrive * The amount of stretch before contraction * The nutrient and oxygen availability * The size of the motor unit

Question 38

A motor neuron makes contact with about ____ muscle fibers

Answer 38

150

Question 39

The total strength of a contraction depends on what

Answer 39

the size of the motor units and the number that are activated

Question 40

Muscle fibers are classified into three main types

Answer 40

* Slow oxidative fibers * Fast oxidative-glycolytic fibers * Fast glycolytic fibers

Question 41

Slow Oxidative fibers

Answer 41

* smallest diameter * least powerful * dark red * aerobic cellular respiration * slow speed of contract * resistant to fatigue * for maintaining posture

Question 42

Fast Oxidative–Glycolytic Fibers (FOG fibers)

Answer 42

* Intermediate in diameter * high amounts of myoglobin * dark red appearance * highly resistant to fatigue * some ATP by anaerobic glycolysis * speed of contraction faster * for walking and sprinting

Question 43

Fast Glycolytic Fibers (FG fibers)

Answer 43

* largest in diameter * most powerful contractions * low myoglobin content * few blood capilaries * few mitochondria * white in color * generate ATP by glycolysis * fatiuge quickly * fibers contract strongly and quickly adapted for intense anaerobic movements of short duration

Question 44

Isotonic contraction

Answer 44

The tension developed remains constant while the muscle changes its length Used for body movements and for moving objects like picking a book up off a table

Question 45

Isometric contraction

Answer 45

The tension generated is not enough for the object to be moved and the muscle does not change its length Holding a book steady using an outstretched arm

Question 46

Ratios of fast glycolytic and slow oxidative fibers are \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

Answer 46

genetically determined