Chapter 6: Muscular System

Question 1

What are the three types of muscle?

Answer 1

cardiac, smooth and skeletal.

Question 2

All muscle cells are elongated and are called ________

Answer 2

muscle fibers

Question 3

All muscle tissues _____

Answer 3

contract

Question 4

Smooth muscles are ______ muscles found
in the walls of many internal organs (digestive
tract, respiratory system, blood vessels).

Answer 4

involuntary

Question 5

Where are smooth muscles found?

Answer 5

walls of many internal organs (digestive

tract, respiratory system, blood vessels).

Question 6

Which muscle Function to aid in the function of other organs?

Answer 6

Smooth

Question 7

Cardiac muscles are ______ muscles found

only in the heart wall.

Answer 7

involuntary

Question 8

How does cardiac muscle function?

Answer 8

Functions by contracting to force blood from the

heart into the arteries

Question 9

Skeletal muscle are ______ muscles attached

to the skeleton.

Answer 9

voluntary

Question 10

Skeletal muscles usually ______

Answer 10

Usually work in pairs

Question 11

Most skeletal muscles are ______ pairs.

Answer 11

antagonistic

Question 12

In antagonistic pairs One muscle _______, the other ______

Answer 12

contracts, relaxes

Question 13

Muscles are attached to the bone by _____

Answer 13

tendons

Question 14

Skeletal muscles are usually attached to two

bones on _____ sides of a joint

Answer 14

opposite

Question 15

The _____ of the muscle is attached to the

bone that remains stationary during movement

Answer 15

origin

Question 16

The ______ is attached to the bone that

moves

Answer 16

insertion

Question 17

What are the functions of skeletal muscles?

Answer 17

1. Support the body – maintain our posture
2. Movement of bones, and other tissues
3. Help maintain a constant body temperature
   – generates heat
4. Helps move blood through the veins and
   lymphatic fluid through the lymphatic
   vessels
5. Help to protect vital organs and stabilize
   joints

Question 18

Muscles are covered by connective tissue

called ______

Answer 18

Fascia

Question 19

What is fascia?

Answer 19

connective tissue that covers the muscle

Question 20

the bundles of

muscle cells are called _____

Answer 20

fascicles

Question 21

______ and _____ are between the fascicles.

Answer 21

Blood vessels and nerves

Question 22

Muscle cells are long cells called _____

Answer 22

muscle fibers

Question 23

The muscle fiber is composed of long thin

_______

Answer 23

myofibrils

Question 24

Myofibrils are bundles of _______ that

contracts.

Answer 24

myofilaments

Question 25

Myofilaments are made of ___ and _______ | filaments.

Answer 25

actin and myosin

Question 26

When muscle fibers are stimulated to contract, myofilaments ______ one another, causing sarcomeres to ______.

Answer 26

slide past, shorten

Question 27

What is the Sarcolemma?

Answer 27

Plasma Membrane

Question 28

______ is similar to cytoplasm, contains | large amount of stored glycogen and myoglobin

Answer 28

Sacroplasm

Question 29

What is Myoglobin?

Answer 29

an oxygen binding protein similar | to hemoglobin, but found only in muscles

Question 30

______ is similar to endoplasmic | reticulum, one of its functions is to store Ca2+

Answer 30

Sarcoplasmic reticulum

Question 31

_____ are extensions of the sarcolemma that come into contact with the sarcoplasmic reticulum.

Answer 31

T-Tubules

Question 32

What kind of cell has multiple nuclei?

Answer 32

Muscle cells

Question 33

_________ is the name for the structural unit | of these myofilaments

Answer 33

Sarcomere

Question 34

The _____ are protein sheets | where the actin filaments attach

Answer 34

Z lines

Question 35

_____ are Thin filaments that formed by two intertwining strands of the protein _____. Attached to the Z line.

Answer 35

Actin, actin

Question 36

_____ are Thick filaments of the protein ______ shaped like a golf club, with a round “head”.

Answer 36

myosin, myosin

Question 37

The myosin heads can bind and detach from the thin actin filament. When bound it creates ________

Answer 37

cross-bridges

Question 38

What are the steps of muscular contraction?

Answer 38

A. An action potential is transmitted through neurons B. Once the action potential reaches the end of a neuron, they release neurotransmitters called acetylcholine C. The neurotransmitters bind to the receptors on the sarcolemma and generate the action potentials D. The action potential travels down the T-tubules, reaching the sarcoplasmic reticulum E. The sarcoplasmic reticulum releases calcium F. Calcium binds to the actin sites G. Actin opens up, so the myosin can attach to them (cross bridges) H. Atp is required for the myosin and actin to slide across each, shortening the sarcomere

Question 39

What is calcium's role in muscle contraction?

Answer 39

Calcium binds to the actin, causing a shift in the complex, opening the sites for myosin to attach.

Question 40

Which of these muscle types is under voluntary control? smooth cardiac skeletal All of the above permit voluntary movement.

Answer 40

skeletal

Question 41

The attachment point of a muscle to the bone that moves is called the ________. insertion origin antagonistic synergistic

Answer 41

insertion

Question 42

Which of the following attaches muscle to a bone? synergistic tetanus ligaments tendons

Answer 42

tendons

Question 43

Which of these structures is an extension of a muscle cell's plasma membrane that delivers signals to the sarcoplasmic reticulum? sarcoplasm T tubule myosin head actin filament

Answer 43

T tubule

Question 44

Which of the following are protein filaments that function in muscle contraction and are attached to the Z line? actin filaments intermediate filaments myosin filaments microtubules

Answer 44

actin filaments

Question 45

Which component of a muscle does the calcium ion combine with to allow a contraction to occur? a structure on the myosin head a structure on the actin the sarcolemma the T tubule

Answer 45

a structure on the actin

Question 46

What is the oxygen binding protein that is found only in muscle cells? gamma globulin myoglobin hemoglobin glutathion

Answer 46

myoglobin

Question 47

The protective sheath of a muscle is called: Myofibrils Fascicles Fascia Sarcolemma

Answer 47

Fascia

Question 48

A bundle of myofilaments is called: Fascicles Myofibrils Sarcolemma Fascia

Answer 48

Myofibrils

Question 49

What is the structural and contractile unit of a skeletal muscle called? Myofilament Sarcolemma Sarcomere Myofibril

Answer 49

Sarcomere

Question 50

A bundle of muscle cells are called ____ Muscle cells/muscle fibers are composed of ______ Myofibrils are composed of ______ The two kinds of myofilaments are : ____ and _____

Answer 50

Fascicles, Myofibrils, Myofilaments, actin and myosin