Chapter 1

Question 1

what is the H zone?

Answer 1

the center of the sacromere where only myosin filaments are located

Question 2

What is A band?

Answer 2

corresponds with the Alignment of myosin filiments

Question 3

what is the I band

Answer 3

has both sides of the actin filiments (has to have both side) It can and will disappear at full muscle contraction when the actin and myosin crossbridge leaving only the actin of the out side of the actin

Question 4

what is the Z line?

Answer 4

the seperation between the actin.

Question 5

resting phase

Answer 5

the muscle is not being stimulated by motor neuron, calcium is in the sarcoplasmic reticulum

Question 6

troponin

Answer 6

oval thing on the actin that want calcium

Question 7

tropomyosin

Answer 7

protien lines in the actin that are attached to the troponon (oval thing that likes calcium) when troponon gets it calcium it attaches to the myosin and tropomyosin helps the cross bridge occur.

Question 8

excitation-contraction coupling phase

Answer 8

toponin decides it needs calcium, calcium is released from the sarcoplasmic reticulum then attaches to the troponin which is attached to the tropomyosin which causes the actin to attach to myosin crossbridges which causes SFT

Question 9

what dictates the force production of a muscle?

Answer 9

the number of cross bridges that are attached to actin filaments

Question 10

contraction phase

Answer 10

the energy of the muscle flexion comes from the breakdown of ATP. As the crossbrige occurs with calcium ADP is continually needed to replace ATP. The muscle keeps contracting if there is enough calcium if not it relaxes

Question 11

what is necessary for myosin cross- bridge cycling with actin filaments?

Answer 11

ATP and calcium

Question 12

recharge phase

Answer 12

as long as calcuim is availble the crossbridge keeps occuring. ATP and ATPase or also available

Question 13

sarcoplasmic reticulum

Answer 13

storing place of calcium

Question 14

relaxation phase

Answer 14

calcium goes back into the sacoplasmic reticulum so the SLT can no longer occur, myosin can no longer attach to the actin because the troponin does not have calcuium in it.

Question 15

fast twitch fibers

Answer 15

type IIa and type IIb

Question 16

slow twitch fibers

Answer 16

type 1

Question 17

type 1 fibers

Answer 17

efficient and fatigue resistant high capactity for anerobic energy supply, limitied potential for rapid force development, low anerobic power

Question 18

type II

Answer 18

inefficient and fatigable, low aerobic ower, rapid force development, high actomyosin, high anerobiv power.

Question 19

difference between type IIa and type IIx(b)

Answer 19

their aerobic oxidative energy supply
type IIa have greater capacity for aerobic metabolism than type IIb
type IIa show greater reisitance to fatigue

Question 20

motor units are composed of ?

Answer 20

muscle fibers that determine thier functional capacity

Question 21

the type of motor unit (fiber type) recruited is determined by its?

Answer 21

physiological characteristics

Question 22

distance running uses ?

Answer 22

slow twitch motor units because they are resistance to fatigue

Question 23

sacropenia

Answer 23

reduced muscle and size in older adults

Question 24

the right side of the heart pumps blood through the ?

Answer 24

lungs

Question 25

the left side of the heart pumps blood throught the ?

Answer 25

rest of the body

Question 26

what prevent the flow of blood from the ventricles back into the atria during ventricular contraction(systole)

Answer 26

the tricuspid valve and mitral valve

Question 27

what prevents backflow from the aorta and pulmonary artieries into the ventricles during ventricular relaxation(diastole)

Answer 27

aortic valve and pulmonary valve

Question 28

what is the sarcoplasm

Answer 28

the cytoplasm of a muscle fiber

Question 29

what is the smallest contractile unit of skeletal muscle

Answer 29

sarcomere where actin and myosin are

Question 30

what runs longitutitly throught the i band

Answer 30

z line

Question 31

the energy from the sliding filiament theory comes from ?

Answer 31

hydolosis of ATP to ADP

Question 32

what is the sequence of events during the SFT

Answer 32

1. binding of calcium to troponin
2. coupling the myosin cross-bridge with actin
3. cross bridge flexion
4. dissociation of actin and myosin
5. recoking of the myosin cross-bridge head