Section 8, Exam 3

Question 1

Surrounds muscle fiber (cell)

Answer 1

Endomysium

Question 2

Surrounds muscle fiber bundle (fasciculus)

Answer 2

Perimysium

Question 3

Surrounds the entire or whole muscle

Answer 3

Epimysium

Question 4

True or False

The epimysium runs continuous with the muscle tendon

Answer 4

True

Question 5

Arteries and veins are oriented ______ to individual muscle fibers.

Answer 5

Parallel

Vessels then branch into many capillaries and venues forming large networks in and around the endomysium

Question 6

Inactive or sedentary men and women have an average of ____ capillaries surrounding each muscle fiber, while athletic or active men and women have an average of ____ capillaries. Thus, physical activity [does/does not] influence muscle perfusion

Answer 6

3-4; 5-6; does not

Question 7

Resting heart muscle blood flow rate is ____mL/min while max exercise heart muscle blood flow rate is ____mL/min.

Answer 7

250; 1000

Question 8

Does heart muscle extract more O2/mL from arterial blood during both resting and max exercise?

Answer 8

No, heart muscle is very dependent on increased blood flow during exercise

Question 9

___% of neurons innervating skeletal muscle are motoneurons, while ___% innervating skeletal muscle are sensory.

Answer 9

60; 40

Question 10

Skeletal muscle are ________ so it can control protein synthesis and can maintain control all along the fiber. _______ are found in diseased muscle cells.

Answer 10

Multi-nuclei; centralized nuclei

Question 11

Space occupied by the thick myosin filament or the length of the myosin filament

Answer 11

A-Band

Question 12

Space between the ends of 2 myosin filaments from adjacent sarcomeres

Answer 12

I-Band

Question 13

Space between the ends of 2 adjacent thin-actin filaments within a sarcomere

Answer 13

H-Zone

Question 14

A dark line seen on electron microscopy in the center of the A-Band which is caused by the overlap of the tail portion of many (400-500) myosin protein molecules.

Answer 14

M-Line

Question 15

Defines the sarcomeres boarder; actin filaments attach here

Answer 15

Z-line (disc)

Question 16

Located just deep to the endomysium; within this structure are nuclei, mitochondria, myoglobin, triglycerides, glycogen, creatine phosphate, and ATP.

Answer 16

Sarcolemma

Question 17

Site of aerobic metabolism

Answer 17

Mitochondria

Question 18

Globular protein binds 1 mole of O2

Answer 18

Myoglobin (1 mole O2 per myoglobin)

Question 19

Substrate (fuel) for aerobic metabolism

Answer 19

Triglyceride (fat)

Question 20

13-15 g/kg of muscle

Answer 20

Glycogen

Question 21

15-17 mM/lg muscle

Answer 21

Creatine phosphate

Question 22

Longitudinal to the myofibril; is a storehouse for Ca2+; contains much greater concentration of Ca2+ than the muscle cell cytoplasm

Answer 22

Sarcoplasmic Reticulum AKA longitudinal tubule

Question 23

Within the sarcolemma, oriented horizontally to the myofibrils

Answer 23

Transverse tubules

Question 24

Within the sarcolemma, oriented along the length of the fiber; contain the actin and myosin filaments oriented within the sarcomeres

Answer 24

Myofibrils

Question 25

A "ball" shaped globular protein molecule

Answer 25

G-actin

Question 26

A strand of "pearls" formed from individual G-actin balls polymerizing; each pear in the stand is a G-actin molecule

Answer 26

F-actin

Question 27

2 F-actin strands make 1 actin linear protein ____

Answer 27

Filament

Question 28

Myosin protein filament consists of _______ linear myosin protein molecules arranged adjacent to one another.

Answer 28

400-500

Question 29

Myosin molecules are _____X larger than Actin

Answer 29

8-9

Question 30

Known as light meromyosin and is 90 nm long

Answer 30

Tail Section

Question 31

Known as heavy meromyosin and is 70 nm long

Answer 31

Head section

Question 32

Joins the tail and head sections of myosin together

Answer 32

hinge region

Question 33

________ molecule swings freely above the hinge region between itself and the adjacent actin protein filament

Answer 33

Head of the myosin

Question 34

T tubules' surfaces are the same as the surface of _____; this is important because it conducts APs

Answer 34

Sarcolemmas

Question 35

Rod-shaped mobile protein about 40 nm long that exists in grooves between actin and myosin filaments

Answer 35

Tropomyosin

Question 36

A globular protein bound to tropomyosin; 1 part of this has a strong affinity to bind to Ca2+

Answer 36

Troponin

Question 37

Prevents the binding of myosin to actin (actomyosin) in resting muscle; Ca2+ in cytoplasm is low = 10^-7 M

Answer 37

Tropomyosin-troponin regulatory complex

Question 38

What happens to troponin binds Ca2+?

Answer 38

tropomyosin moves or rolls on F-actin, allowing myosin and actin to bond; Ca2+ in cytoplasm increases to about 10^-5 M during muscle contraction

Question 39

Where does hydrolysis of ATP take place?

Answer 39

On the head of myosin