Muscular System

Question 1

What is a contractile tissue and has diverse functions?

Answer 1

Muscles

Question 2

What are some functions of muscles?

Answer 2

Locomotion, respiration, digestion, parturition, blood and lymph circulation, swallowing, generation of body heat

Question 3

Specific properties of muscles?

Answer 3

Contractility
Excitability
Extensibility
Elasticity

Question 4

What is contractility?

Answer 4

Ability to contract or shorten

Question 5

What is Excitability?

Answer 5

Ability to receive and respond to a stimulus

Question 6

What is Extensibility?

Answer 6

Ability to be stretched

Question 7

What is Elasticity?

Answer 7

Ability to return to original shape after being stretched

Question 8

What are the 3 types of muscles?

Answer 8

Skeletal: 40% of body

Cardiac and Smooth: 10% of body

Question 9

Which muscle contracts slowly, is found in viscera & blood vessels, and is involuntary?

Answer 9

Smooth Muscle (Visceral)

Question 10

Which muscle contracts rapidly, is found in head, neck, trunk, and extremities, and is voluntary?

Answer 10

Skeletal Muscle (Striated)

Question 11

Which muscle contracts rapidly, is found in the heart, and is involuntary?

Answer 11

Cardiac Muscle

Question 12

Which factors are crucial for body movement?

Skeletal muscle

Answer 12

• Attached to bones
• Usually by tendons
• Moves and supports the skeleton
• Is stimulated by a motor nerve

Question 13

Body movement is the result of what?

Answer 13

Contraction of skeketal muscle across a movable

joint

Question 14

T/F: Most joints have one or more muscles on both sides either to increase or decrease its angle

Answer 14

True

Question 15

What are the 5 skeletal muscles?

Answer 15

Flexors
Extensors
Abductors
Adductors
Sphincters

Question 16

Which skeletal muscle type DECREASES the joint angle?

Answer 16

Flexors

Question 17

Which skeletal muscle type INCREASE the joint angle?

Answer 17

Extensors

Question 18

Which skeletal muscle type pulls limbs AWAY from the median plane?

Answer 18

Abductors

Question 19

Which skeletal muscle type pulls limbs TOWARDS the median plane?

Answer 19

Abbductors

Question 20

Which skeletal muscle type are arranged circularly to constrict body openings?

Answer 20

Sphincters

Question 21

What are the levels of organization for skeletal muscle?

Answer 21

1. Epimysium and Fascicle
2. Perimysium and Endomysium
3. Sarcolema and Muscle Fibers
4. Myofibrals and Sarcomeres

Question 22

What is a sheath of connective tissue surrounding the

muscle

Answer 22

Epidmysium

Question 23

What is a small bundle or cluster of muscle fibers

cells

Answer 23

Fascicle

Question 24

What are connective tissue extensions from the

epimysium that surround each fascicle

Answer 24

Perimysium

Question 25

What are connective tissue extensions from the perimysium that surround the muscle fibers and are attached to the sarcolemma

Answer 25

Endomysium

Question 26

What is: • A thin cell membrane enclosing a skeletal muscle fiber (cell) • At each end of the muscle fibers, sarcolema fuses with tendon fibers – collect into bundles to form muscle tendons – connect the muscles to the bones

Answer 26

Sarcolema

Question 27

What are: • Muscle cells – alongated shape, multinucleated (MORPHOLOGICAL SYNCYTIUM) • the contractile unit

Answer 27

Muscle Fibers

Question 28

T/F: The pull in muscle fibers is transmitted by endomysium, perimysium and epimysium to tendon or aponeurosis that is attached to a bone

Answer 28

True

Question 29

What is composed by a linear series of | repeating sarcomeres?

Answer 29

Myofibrils

Question 30

What: • Basic contractile unit of striated muscle fibers • Found between Z LINES or Z disks • Contain protein myofilaments called actin and myosin • Their arrangement give rise to striations

Answer 30

Sarcomeres

Question 31

What are responsible for actual muscle contractions?

Answer 31

Myofilaments

Question 32

Which filament is composed of actin, troponin, and tropomyosin?

Answer 32

Thin myofilament

Question 33

Which filament is composed of myosin?

Answer 33

Thick myofilament

Question 34

What causes myofibrils to have striations?

Answer 34

Myosin and actin filaments

Question 35

What are the organelles of the muscle cell?

Answer 35

Sarcoplasmic reticulum | Mitochondria

Question 36

Which organelle regulates Ca+ storage, release and uptake, and is important for muscle contraction?

Answer 36

Sarcoplasmic reticulum

Question 37

Which organelle supplies contracting myofibrils with large amounts of E in form of ATP?

Answer 37

Mitochondria

Question 38

What allows the plasma membrane of the muscle fiber to carry the depolarization of the action potential to the interior of the fiber?

Answer 38

T tubules