Physiology Exam 2 Lecture 14

Front 1

which two types of muscle are striated

Back 1

cardiac and skeletal

Front 2

during devlopment, ____ or undifferentiated mononucleated cells fuse into a single cylindrical mutlinucleated cell

Back 2

myoblasts

Front 3

definition. a single skeletal muscle cell

Back 3

muscle fiber

Front 4

what are the two important factors following skeletal muscle damage

Back 4

satellite cells and muscle hypertrophy

Front 5

definition. dark band parallel arrangement and alignment of thick and thin filaments

Back 5

A band

Front 6

H zone

Back 6

narrow light band corresponding to the space between the opposing ends of two sets of thin filaments

Front 7

I band =

Back 7

light band

Front 8

definition. contains the regions of thin filaments that do not overlap heavy filaments

Back 8

I band or light band

Front 9

defintiion. network of itnerconnecting proteins that anchors thin filaments at the boundary of each sarcomere

Back 9

z line

Front 10

proteins that link the central region of adjacent thick filaments

Back 10

M line

Front 11

definition. elastic protein that extends from the Z line to the M line and is linked to both the M line proteins and thick filaments act to maintain the alignment of thick filaments in the middle of each sarcomere

Back 11

titin

Front 12

each myosin can interact wiht how many actin

Back 12

six

Front 13

each actin can interact with how many myosin

Back 13

3

Front 14

definition. myosin binds to actin and slides it pulling the z lines closer together and reducing the width of the i bands

Back 14

contraction or shortening

Front 15

do filament lengths change in contraction?

Back 15

no only overlapping increases

Front 16

what is reduced in muscle contraction

Back 16

HI

Front 17

what stays the same in muscle contraction

Back 17

A

Front 18

can you have contractions without shortening?

Back 18

yes like isometric exercise

Front 19

definition. thick filament that is actually a polymer of myosin molecuels each of which has a flexible cross bridge and that binds ATP and actin

Back 19

myosin

Front 20

definition. calcium binding protein. calcium causes a confromation change which affects tropomyosin and exposes actin for ginding

Back 20

troponin

Front 21

cross bridge cannot be released becasue no ATP is made

Back 21

after death rigor mortis

Front 22

in relaxed skeletal muscle, ____ blocks the cross bridge binding site on actin

Back 22

tropomyosin

Front 23

contraction occurs when _____ bind to troponin; this complex then pulls tropomyosin away from the cross bridge binding site

Back 23

calcium ions

Front 24

what does the latent period between excitation and development of tension in msucle include

Back 24

time to release calcium from sarcoplasmic reticulum
move tropomyosin \cycl the corss bridge

Front 25

the sarcoplasmic reticulum is continuous with the ___ ____

Back 25

endoplasmic reticulum

Front 26

where is calcium stored

Back 26

lateral sacs

Front 27

what receptors release calcium into the lateral sac

Back 27

DHP and ryanodine receptors which are both voltage sensitive

Front 28

where are DHP and ryanodine receptors found

Back 28

T tubules

Front 29

how is caclium taken back into the lateral sack

Back 29

primary active transport

Front 30

what does calcium bind to

Back 30

troponin which makes a conformationl change on tropomyosin

Front 31

what are the three functions of ATP in skeletal muscle

Back 31

energize the cross bridge
dissociate the cross bridge
energy for active transport of caclium into the reticulum lowering cytosolic calcium to prerelase levels ending the contraction and allowing the muscle fiber to relax

Front 32

definition. motor neuron and all of the fibrils it innervates

Back 32

single motor unit

Front 33

how may motor neurons will a fibril receive a synapse from

Back 33

a single motor neuron

Front 34

why are muscles not all or none

Back 34

more can be recruited to reach full contraction ... there is not always full contraction

Front 35

definition. the point of synaptic contact between the axon terminal or a motor neuron and the muscle fiber it controls

Back 35

neuromuscular junction

Front 36

definition. analogous to an EPSP

Back 36

EPP

Front 37

what does metric mean

Back 37

length

Front 38

definition. responds well to repetitive stimulation without becomign fatigued muscles of the body posure are examples

Back 38

slow oxidative skeletal muscle

Front 39

defintiion. responsds quickly and to repetitive stimulation without becomign fatigued

Back 39

fast oxidative muscles

Front 40

defintiion. used fro quick bursts of strong activation

Back 40

fast glycolytic skeletal muscle

Front 41

walking is an example of what kind of muslce

Back 41

fast oxidative

Front 42

jumping is an example of what kind of muscle

Back 42

fast glycolytic

Front 43

which skeletal muscles are the smallest

Back 43

slow oxidative

Front 44

which skeletal muscles are the whitest

Back 44

fast glycolytic