Ch 10

Question 1

an alternate name for a skeletal muscle

Answer 1

muscle fibers

Question 2

a property of a cell in which it is responsive in the presence of various stimuli

Answer 2

excitable

Question 3

a property of a cell by which it can be stretched without sustaining damage

Answer 3

distensible

Question 4

a property of a cell by which it will return to its resting length after it’s been stretched

Answer 4

elasticity

Question 5

the cytoplasm of a muscle fiber

Answer 5

sarcoplasm

Question 6

the plasma membrane of a muscle fiber

Answer 6

sarcolemma

Question 7

long, cylindrical organelles composed of muscle protein in a muscle fiber

Answer 7

myofibrils

Question 8

the specialized smooth endoplasmic reticulum of a muscle fiber that stores calcium ion

Answer 8

sarcoplasmic reticulum

Question 9

hollow inward extensions of a muscle fiber sarcolemma that surround myofibrils; filled with extracellular fluid

Answer 9

transverse tubules (t-tubules)

Question 10

enlarged regions of the sarcoplasmic reticulum where it contacts t-tubules

Answer 10

terminal cisternae

Question 11

a t-tubules and two adjacent terminal cisternae in a muscle fiber

Answer 11

triad

Question 12

muscle protein that make up myofibril in a muscle fiber

Answer 12

myofilaments

Question 13

a myofilament composed of many molecules of the protein myosin

Answer 13

thick filament

Question 14

a clube shaped contractile protein found in a muscle fibers and cells that are motile

Answer 14

myosin

Question 15

a myofilament composed of molecules of the protein actin, troponin, and tropomyosin

Answer 15

thin filament

Question 16

a bead shaped contractile protein found in muscle fibers and motile cells

Answer 16

actin

Question 17

a filamentous regulatory protein that covers the active sites of actin subunits in a thin filament

Answer 17

tropomyosin

Question 18

a regulatory protein with three subunits that binds tropomyosin and calcium ions in a thin filament

Answer 18

troponin

Question 19

a myofilament that consist of the structural protein titin

Answer 19

elastic filament

Question 20

the component of the sarcomere that appears lighter because it only contains thin filaments

Answer 20

I bands

Question 21

the component of the sarcomere that appears darker because it contains thick filaments and areas in which the thick and thin filaments overlap

Answer 21

A bands

Question 22

the components of the sarcomere that contains structural proteins to which thin and elastic filaments attach

Answer 22

Z disc

Question 23

the functional unit of muscle contraction; consists of an area of the myofibril from one z-disc to the next z-disc

Answer 23

sarcomere

Question 24

the mechanism of contraction of a muscle cell in which thin and thick filaments slide past one another while generating tension

Answer 24

sliding-filament mechanism

Question 25

the study of electrical changes in the body’s cells and the physiological processes that accompany these changes

Answer 25

electrophysiology