Muscle Module Discussion 1 Notes

Question 1

_____________ is the general function of muscle that that functions as a form of storage of sugar and high energy molecules

Answer 1

chemical energy storage

Question 2

__________________ is a general function of muscle that allows us to produce force and use ATP

Answer 2

Transduction and conversion of chemical energy to mechanical energy

Question 3

What are the three types of muscle

Answer 3

voluntary striated, unvioluntary striated, involuntary unstraiated

Question 4

Function and name of voluntary striated muscle

Answer 4

skeletal muscle

locamotion and posture

Question 5

Function and name of involuntary striated muscle

Answer 5

cardiac muscle

cardiac pump

Question 6

Function and name of unstriated involuntary muscle

Answer 6

smooth muscle

digestion, visual accommodation, thermoregulation

Question 7

What is the structure of muscle

Answer 7

whole muscle -> muscle fiber -> myofibril -> sarcomere

Question 8

What are the structural notes of a muscle fiber

Answer 8

• indiviudal muscle cell
• diameter 50 μm
• length of whole muscle
• multinucleate

Question 9

What are the structural notes of a myofibril

Answer 9

• contractile organelle
• diameter 1μm
• length whole muscle fiber

Question 10

What are the structural notes of a sarcomere

Answer 10

• contractile unit
• one sarcomere can contract and produce force on its own
• length 2.1 μm

Question 11

What are the connective tissue layers in muscle

Answer 11

• Epimyseim: surrounds whole muscle
• perimyseium: surrounds groups of muscle fibers
• endomyseium: surrounds individual muscle fibers

Question 12

what is the connective tissue of muscles primarily made of

Answer 12

collagen (elastic and strong)

Question 13

_________ surrounds whole muscle

Answer 13

-Epimyseim:

Question 14

______________ surrounds groups of muscle fibers

Answer 14

perimyseim

Question 15

________________ surrounds individual muscle fibers

Answer 15

-endomyseium:

Question 16

Structural units of a sarcomere:

Answer 16

• Z disc
• M line
• A band
• I band

Question 17

Structural units of a sarcomere:

___________ beginning and end of sarcomere. Archiores thin filament

Answer 17

Z disc

Question 18

Structural units of a sarcomere:

__________ is the midline of sarcomere

Answer 18

Midline

Question 19

Structural units of a sarcomere:

__________________ region containing only thick myfilaments

Answer 19

A band

Question 20

Structural units of a sarcomere:

_________________ region containing only thin filaments

Answer 20

I band

Question 21

_____________ are what contain contractile proteins in sarcomere

Answer 21

myofilaments

Question 22

Length of filaments:

Answer 22

thick filament: length 1.6 μm

thin filament length 1.0 μm

Question 23

what were experimenters unsure was due to________________

Answer 23

shortening of thin filaments or sliding filaments

Question 24

An experimenter was done to understand how muscle contraction works

Answer 24

• stimulate the muscle to contract
• measured force generated by the muscle
• Increase in the length of the muscle

Question 25

Sliding filament hypothesis: | Overall change in length during contraction

Answer 25

- muscle fiber, myofibral, sarcomere gets shorter | - filament do not change, they overlap

Question 26

____________________ are structural connections between thick and thin filaments. Thought to be motors producing force during contraction

Answer 26

structural connections

Question 27

Thin filaments are made of

Answer 27

- G action - Trpomyosin - ttroponin Complex

Question 28

In thin filaments: ______________: -Is globular -forms an alpha helical polymer -7G actin make up one turn of the alpha helix -a polymer associated to make a double strand of F actin

Answer 28

G actin

Question 29

How many G actin make up one turn of the alpha helix

Answer 29

7 G actin

Question 30

``` In thin filaments: ____________ -Is long and helical -7 G actin long -associated with F actin ```

Answer 30

Tropomyosin

Question 31

In thin filaments: ______________ -50 long -spherical

Answer 31

Troponin Complex

Question 32

What make a thick filament?

Answer 32

- Myosin heavy chain | - myosin light chain

Question 33

``` In thick filaments?: ____________: -head of ATP -Tail of alpha helix -form dimers ```

Answer 33

myosin heavy chains

Question 34

In thick filaments?: ______________________ -self autonomous (assemble by themselves) -staggered one after another -antiparallel on either side of each other fragmenting in either direction

Answer 34

myosin light chains

Question 35

_____________ where the thick filament myosin head is attached to thin filament G actin

Answer 35

cross bridge

Question 36

Purpose of cross bridge cycle is to _____________ with ______________

Answer 36

cause a force production | with ATP and CA2+

Question 37

In the cross bridge cycle: during the _________________ -low Ca levels, myosin heavy chain head is relaxed, and ATP is hydrolyzed -cross bridge is not formed

Answer 37

relaxed state

Question 38

what is the first step of the cross bridge cycle

Answer 38

1. an increase in intracellular Ca2+

Question 39

How are cross bridge formed

Answer 39

- myosin heavy chain head binds to thin filament | - ATP is still hydrolyzed in form of ADP and P

Question 40

What is the power stroke aka tiger state

Answer 40

- realse of ADP and P which causes conformational changes in the MHC head - MHC head remains bound but changes its angle at hinge region

Question 41

what happens in the cross bridge cycle after the power stroke

Answer 41

- release of head from thin strand - ATP binds to MHC - MHC dissociated from thin filaments still at angle

Question 42

What is the final step of the cross bridge cycle

Answer 42

hydrolysis of ATP | -this causes MHC head to be relaxed again and go back to relaxed state

Question 43

one cross bridge cycle is an unload in muscle that takes _________________

Answer 43

50 msecs

Question 44

MHC head ____________ on each half of sarcomere

Answer 44

moves 10nm

Question 45

Power streak causes __________________ and ___________________

Answer 45

- moves Z disc toward M line | - causes 20 nm total per sarcomere

Question 46

efficency is ______________ of chemical energy is transduced Into mechanical energy

Answer 46

45% of energy

Question 47

_____________ is the hydrolysis of ATP breaking its phosphate bond

Answer 47

chemical energy

Question 48

Where is the chemical energy stored ____________

Answer 48

MHC head

Question 49

what happens to the chemical energy

Answer 49

it is released as mechanical energy when the MHC head moves

Question 50

what happens to chemical energy

Answer 50

55% is lost as heat aka thermoregulation