ch17

Question 1

connective tissue surrounding entire muscle

Answer 1

epimysium

Question 2

connective tissue surrounding bundles of muscle fibers (fasciculi, fascicle)

Answer 2

perimysium

Question 3

surrounds individual muscle fibers

Answer 3

endomysium

Question 4

storage sites for calcium and contain terminal cisternae (lateral sacs)

Answer 4

sarcoplasmic reticulum

Question 5

inside cytoplasm and contains transverse tubules [carry electrical signal to releasle Ca]

Answer 5

sarcoplasm : transverse tubules

Question 6

thick filaments include __: reactive sites that create crossbridges and have a rodlike tail

Answer 6

myosin

Question 7

___ filaments are actin, tropomyosin, and troponin

Answer 7

thin

Question 8

3 subunits of troponin is

Answer 8

tn-C
tn-T
tn-I

Question 9

troponin subunit that contains Ca binding sites

Answer 9

Tn-C

Question 10

troponin subunit that binds to tropomyosin

Answer 10

tn-T

Question 11

troponin subunit that inhibits binding of actin/myosin during rest

Answer 11

tn-I

Question 12

1. neuron action potential arrives at end of motor neuron
2. ach is released
3. ach binds to receptors on motor end plates
4. sodium ions rush into muscle fibers
5. muscle action potentioal sweeps into t tubules
6. sr releases ca
7. ca binds to troponin
8. when ca binds to troponin, causes tropomyosin to shift and expose myosin binding site
9. myosin binds to actin
10. myosin pivots, pulling actin filaments
11. myosin releases form actin
12. myosin reextends to ready position

Answer 12

muscle contraction

Question 13

1. force of contrafction is generated by the process that slides the actin filament over the myosin filament
2. lengths of the thick and thin filaments do not change during muscle contraction
3. length of the sarcomere decreases as the actin filaments slide over myosin filaments and pull the z discs toward the center of the sarcomere

Answer 13

sliding filament theory basic principles

Question 14

• 2 z lines
• I band =actin filaments achored to z lines
• A band=myosin filaments with some actin overlapped
• H zone has no actin present

Answer 14

sarcomere at REST

Question 15

• actin filaments slide over myosin Filaments
• z lines pulled towards center
• I band shortens
• A band length doesnt change
• H zone disappears
• neither filament changes in length

Answer 15

sarcomere CONTRACTED

Question 16

ATP is required for muscle contraction and the myosin ATPase is located on ___ of myosin crossbridge. breakdown of ATP releases energy for movement of crossbridge

Answer 16

head

Question 17

sources of ATP include : ___,___,and ___

Answer 17

phosphagens, glycolysis

, oxidative phosphorylation

Question 18

• rest
• spread of depolarization
• binding of calcium to troponin
• generation of force

Answer 18

Phases of ECC

Question 19

crossbridge of myosin heads extend toward actin , ATP molecule is bound to crossbridge and tropomyosin blocks active sites on actin molecule during ___

Answer 19

rest phase of ECC

Question 20

2. action potential - nerve junction, ACh cross NM junction, receptors to sarcolemma and t-tubles to SR
3. Calcium release to lateral sacs

Answer 20

phase 1 of ECC

Question 21

calcium binds to Tn-C

• positional change
• active sites uncovered

Answer 21

phase 2 of ECC

Question 22

-crossbridge cycling generates force, filaments slide past, and z lines drawn together

Answer 22

phase 3 of ECC

Question 23

1. cross bridge formation
2. powerstroke myosin head swivel
   3.separation of myosin and actin
   when atp binds to myosin
   4.activation of myosin heads when breakdown of ATP

Answer 23

crossbridge cycling

Question 24

long thin protein in actin filament is known as

Answer 24

tropomyosin

Question 25

end of the myosin cross bridge is known as

Answer 25

myosin head

Question 26

1. rest 2. excitation coupling 3. contraction 4. recharging

Answer 26

phases of muscle contraction

Question 27

distance between 2 z lines is called

Answer 27

sarcomere

Question 28

length of the i band during contraction ____

Answer 28

shortens

Question 29

motor nerve impulse ach released sarcolemma stimulated

Answer 29

3,1,2

Question 30

actomyosin crossbridge formation, ATPase action, powerstroke

Answer 30

2,1,3

Question 31

cisternae stimulated calcium travels to actin atp and calcium attracted

Answer 31

1,3,2

Question 32

within sarcomere ,thick filaments runs the entire length of the a band and the a band is interrupted in the mid section by the h zone where there is no overlap of thick/thin filaments

Answer 32

true

Question 33

troponin inhibits myosin from binding motor nerve impulse actomyosin formed

Answer 33

2,3,1

Question 34

actomyosin formed ATPase crossbridge powerstroke swivel

Answer 34

sliding filament theory

Question 35

crossbridge swivels, motor nerve impulses cease cacium pumped back into terminal cisternae

Answer 35

true

Question 36

ATPase breakdown ATP release 12kcals

Answer 36

true