Muscle tissue and organization

Question 1

Excitability

Answer 1

Ability of a muscle to respond to a stimuli

Question 2

Conductivity

Answer 2

Ability of a muscle to transmit electrical signals along the cell membrane

Question 3

Contractivity

Answer 3

Ability of a muscle to create tension and shorten cell length

Question 4

Elasticity

Answer 4

Ability of a muscle to return to resting length

Question 5

Extensibility

Answer 5

Ability of a muscle to be stretched beyond resting length

Question 6

Fascicle

Answer 6

Bundle of muscle fibers

Question 7

Myofibrils

Answer 7

Inside individual muscle fibers

Question 8

Myofilaments

Answer 8

What myofibrils are composed of (Actin and myosin)

Question 9

Organization of skeletal muscles (smallest to largest)

Answer 9

Myofilaments, myofibrils, muscle fiber, fascicle, skeletal muscle

Question 10

Endomysium

Answer 10

Surrounds and insulates each muscle fiber (areolar CT and reticular fibers)

Question 11

Perimysium

Answer 11

Surrounds fascicles (dense irregular CT)

Question 12

Epimysium

Answer 12

Surrounds entire muscle (dense irregular CT)

Question 13

Tendon

Answer 13

Cord-like structure that’s formed by the CT layers

Question 14

Aponeurosis

Answer 14

Sheet-like structure that’s thin and flattened CT attachment

Question 15

Sarcolemma

Answer 15

Plasma membrane that covers muscle fibers

Question 16

Sarcoplasm

Answer 16

Cytoplasm in between myofibrils

Question 17

Sarcoplasmic reticulum (SR)

Answer 17

Within the smooth ER and stores calcium ions to initiate a muscle contraction

Question 18

Transverse tubules

Answer 18

Deep invaginations of sarcolemma for passage of nerve impulses

Question 19

Terminal cisternae

Answer 19

Expanded ends of SR

Question 20

Triad

Answer 20

2 terminal cisternae and 1 transverse tubule

Question 21

I-Band

Answer 21

Only thin filaments

Question 22

Sarcomere

Answer 22

Functional unit of skeletal muscle

Question 23

A-Band

Answer 23

Think and thin filaments

Question 24

H-Zone

Answer 24

Center of A-Band (thick filament only)

Question 25

M-line

Answer 25

Center of H-Zone (thick filaments attach)

Question 26

Z disc

Answer 26

Center of I-Band (thin filaments attach)

Question 27

How does the structure of the sarcomere change as muscle contraction occurs?

Answer 27

Thick filaments attach to thin filaments and pull them toward the center of the sarcomere

Question 28

Proteins that form a thin filament

Answer 28

F-actin, G-actin, nebulin, tropomyosin, troponin complex

Question 29

Nebulin

Answer 29

Actin-binding protein

Question 30

Tropomyosin

Answer 30

Double-stranded regulatory protein

Question 31

Troponin complex

Answer 31

Regulatory protein that has a binding site for calcium

Question 32

Synaptic knob (drawing)

Answer 32

Tip of telodendria

Question 33

Synaptic vesicles (drawing)

Answer 33

Membrane sacs in synaptic knob, filled with ACh

Question 34

Synaptic cleft (drawing)

Answer 34

Narrow space separating synaptic knob and motor end plate

Question 35

Motor end plate (drawing)

Answer 35

Region of sarcolemma with many folds

Question 36

Neurolemocyte (drawing)

Answer 36

Just above synaptic knob (produces myline)

Question 37

Circular muscle fibers

Answer 37

Formed around an opening (orbicularis oris)

Question 38

Parallel muscle fibers

Answer 38

Fascicles are parallel to the axis of the muscle (rectus abdominis)

Question 39

Covergent muscle fibers

Answer 39

Triangular muscle with common attachment site (Pectoralis major)

Question 40

Pennate muscle fibers

Answer 40

Muscle body has one or more tendons

Question 41

Unipennate muscle fibers

Answer 41

All muscle fibers on the same side of the tendon (extensor digitorum)

Question 42

Bipennate muscle fibers

Answer 42

Muscle fibers on both sides of the tendon (rectus femoris)

Question 43

Multipennate muscle fibers

Answer 43

Tendon branches within the muscle (Deltoid)