Ch 11- Musculoskeletal

Question 1

“Bones are more than simply a support structure, however; they also provide

Answer 1

protection to internal organs, serve as a storage reserve of calcium and other minerals, and are the site of hematopoiesis.”

Question 2

“Rapid muscle contraction also leads to shivering, which is important in

Answer 2

thermoregulation. ”

Question 3

“Muscle can be divided into the three different subtypes:

Answer 3

skeletal muscle, smooth muscle, and cardiac muscle.”

Question 4

“Skeletal muscle is responsible for voluntary movement and is therefore innervated by the _________ nervous system”

Answer 4

Somatic

Question 5

“Due to the arrangement of actin and myosin into repeating units called ________, it appears striped or striated when viewed microscopically.”

Answer 5

Sarcomeres

“Skeletal muscle is multinucleated”

Question 6

_______ Have high myoglobin content and primarily derive their energy aerobically”

Answer 6

“Red fibers, also known as slow-twitch fibers

“also contain many mitochondria to carry out oxidative phosphorylation”

Muscles that contract slowly, but that can sustain activity (such as the muscles that support posture), contain a predominance of red fibers”

Question 7

An oxygen carrier that uses iron in a heme group to bind oxygen, imparting a red color”

Answer 7

Myoglobin

Question 8

_______ contain much less myoglobin. Because there is less myoglobin, and therefore less iron, the color is lighter.”

Answer 8

White fibers, also known as fast-twitch fibers

Question 9

Muscles that contract slowly, but that can sustain activity (such as the muscles that support posture), contain a predominance of

Answer 9

Red fibers

Question 10

“Muscles that contract rapidly, but fatigue quickly, contain mostly

Answer 10

White fibers

Question 11

“have a single nucleus located in the center of the cell

Answer 11

Smooth muscle

Question 12

“Just like skeletal muscle, smooth muscle cells contain _________, but the fibers are not as well-organized, so striations cannot be seen”

Answer 12

Actin and myosin

Question 13

“ Compared to skeletal muscle, smooth muscle is capable of more sustained contractions; a constant state of low-level contraction, as may be seen in the blood vessels, is called

Answer 13

Tonus

Question 14

“Smooth muscle can actually contract without nervous system input in what is known as

Answer 14

myogenic Activity

Question 15

“both smooth and cardiac muscle exhibit _______. These muscle cells will respond to nervous input, but do not require external signals to undergo contraction.”

Answer 15

myogenic Activity

Question 16

“Cardiac muscle cells are connected by intercalated discs, which contain many

Answer 16

Gap junctions

“These gap junctions are connections between the cytoplasm of adjacent cells, allowing for the flow of ions directly between cells. This allows for coordinated muscle cell depolarization and efficient contraction of cardiac muscle”

Question 17

“One of the ways epinephrine does increases HR and contractility is by increasing intracellular ______ levels within cardiac myocytes.”

Answer 17

Calcium

Question 18

“The _______ is the basic contractile unit of skeletal muscle”

Answer 18

Sarcomere

Question 19

Troponin and tropyosin are associated with which filament

Answer 19

Actin

“To remember which filament is associated with troponin and tropomyosin, remember that actin has a T in it.”

Question 20

________ define the boundaries of each sarcomere. ”

Answer 20

Z- Lines

“Z—Z is the end of the alphabet, and the end of the sarcomere
M—in the middle of the myosin filaments
I—I is a thin letter (thin filaments only)
H—H is a thick letter (thick filaments only)
A—all of the thick filament, whether or not it is overlapping”

Question 21

runs down the center of the sarcomere, through the middle of the myosin filaments”

Answer 21

M-Line

“Z—Z is the end of the alphabet, and the end of the sarcomere
M—in the middle of the myosin filaments
I—I is a thin letter (thin filaments only)
H—H is a thick letter (thick filaments only)
A—all of the thick filament, whether or not it is overlapping”

Question 22

“The ________ is the region containing exclusively thin filaments, whereas the ______ contains only thick filaments.”

Answer 22

I Band, H-Zone

“Z—Z is the end of the alphabet, and the end of the sarcomere
M—in the middle of the myosin filaments
I—I is a thin letter (thin filaments only)
H—H is a thick letter (thick filaments only)
A—all of the thick filament, whether or not it is overlapping”

Question 23

The _______ contains the thick filaments in their entirety, including any overlap with thin filaments

Answer 23

A- Band

“Z—Z is the end of the alphabet, and the end of the sarcomere
M—in the middle of the myosin filaments
I—I is a thin letter (thin filaments only)
H—H is a thick letter (thick filaments only)
A—all of the thick filament, whether or not it is overlapping”

Question 24

“Sarcomeres are attached end-to-end to form ______ and are surrounded by a covering known as the _________, a modified endoplasmic reticulum that contains a high concentration of Ca2+ ions”

Answer 24

myofibrils, Sarcoplasmic Reticulum

Question 25

“The ________ is a modified cytoplasm located just outside the sarcoplasmic reticulum”

Answer 25

Sarcoplam

Question 26

“The cell membrane of a myocyte is known as the

Answer 26

sarcolemma

“The sarcolemma is capable of propagating an action potential and can distribute the action potential to all sarcomeres in a muscle using a system of transverse tubules”

Question 27

“The sarcolemma is capable of propagating an action potential and can distribute the action potential to all sarcomeres in a muscle using a system of

Answer 27

transverse tubules (T-Tubules)

Oriented perpendicular to myofibrils

Question 28

“Each ______, or muscle cell, contains many myofibrils arranged in parallel and can also be called a ________”

Answer 28

Myocyte, Muscle Fiber

Question 29

“A myofibril is an arrangement of many _______ in series. ”

Answer 29

Sarcomeres

“A muscle fiber (or myocyte, or muscle cell) contains many myofibrils within it, arranged in parallel. A muscle is made up of parallel muscle fibers”

Question 30

Muscle contraction depends on

Answer 30

ATP and Calcium

Question 31

3 Major steps of muscle contraction

Answer 31

Initiation, Contraction, Relaxation

Question 32

“Addition of multiple simple twitches before the muscle has an opportunity to fully relax is called

Answer 32

frequency summation

Question 33

“Simple twitches that occur so frequently as to not let the muscle relax at all can lead to ______, a more prolonged and stronger contraction.”

Answer 33

frequency summation

Question 34

“Muscle cells have additional energy reserves to reduce _____ (the difference between the amount of oxygen needed and the amount present) and forestall fatigue.”

The 2 energy reserves are ____ and _____

Answer 34

Oxygen debt, Creatine Phosphate and Myoglobin

“Creatine phosphate can transfer a phosphate group to ADP, forming ATP.
Myoglobin is a heme-containing protein that is a muscular oxygen reserve.”

Question 35

“Internal skeletons (like those in humans) are called ______; external skeletons (like those in arthropods) are called ______.”

Answer 35

Endoskeletons, Exoskeleton

Question 36

“The human skeletal system can be divided into ___ And _____ skeletons

Answer 36

axial and appendicular skeletons.”

Question 37

“The ______ skeleton consists of structures in the midline such as the skull, vertebral column, ribcage, and hyoid bone.”

Answer 37

Axial

Question 38

“The ______skeleton consists of the bones of the limbs, the pectoral girdle, and the pelvis.”

Answer 38

appendicular

Question 39

“Spongy or cancellous bone has a lattice-like structure consisting of bony spicules known as _______. The cavities are filled with ______.”

Answer 39

trabecular, bone marrow

Question 40

“Bone matrix has both _______ components, like collagen, glycoproteins, and other peptides, and ______ components, like hydroxyapatite.”

Answer 40

Organic, Inorganic

Question 41

______ also increases resorption of bone, leading to increased turnover and, subsequently, the production of stronger bone.”

Answer 41

Vitamin D

Question 42

“Cartilage is a firm, elastic material secreted by chondrocytes. Its matrix is called

Answer 42

Chondrin

Question 43

“In fetal life, bone forms from cartilage through _______ Some bones, especially those of the skull, form directly from undifferentiated tissue (mesenchyme) in _______

Answer 43

endochondral ossification, intramembranous ossification

Question 44

______ are fused together to form sutures or similar fibrous joints.”

Answer 44

“Immovable joints

Question 45

2 types of joints

Answer 45

Movable, immovable

Question 46

“Movable joints are usually strengthened by ligaments and contain a ______

Answer 46

Synovial Capsul

Question 47

_________, secreted by the synovium, aids in motion by lubricating the join”

Answer 47

Synovial Fluid

Question 48

“Each bone in the joint is coated with ________ to aid in movement and provide cushioning.”

Answer 48

articular cartilage

Question 49

“Muscles that serve opposite functions come in _________; when one muscle contracts, the other lengthens.”

Answer 49

antagonistic pairs

Question 50

In muscle contraction what happens when atp is hydrolyzed

Answer 50

Myosin head recocks

Question 51

In muscle contraction what happens when ADP and Pi dissociate

Answer 51

Sarcomere contracts power stroke occurs

Question 52

In muscle contraction what happens when a new ATP bins to myosin

Answer 52

Causes detachment of myosin from actin