Exam 2 Muscle Structure Flashcards Preview

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Flashcards in Exam 2 Muscle Structure Deck (30)
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1

how many muscles in a carcass

over 600

2

tendon

-bind muscle to bone
-skeletal muscle

3

ligaments

-bind bone to bone
-joint capsule

4

connective tissue layers

-endomysium covered by the
-perimysium covered by the
-epimysium

5

what is the most abundant muscle protein

myosin

6

thick filament

myosin (yellow inside)

7

thin filament

actin (black horizontal line)

8

sarcoplasmic reticulum

organelle that regulates calcium

9

sarcolemma

membrane covering a muscle fiber

10

t-tubules

invaginations that allow depolarization of the membrane

11

motor neurons

axons that control muscle

12

blood vessels

transports blood/ oxygen to the muscles

13

action potential

-a short-lasting event in which the electrical membrane potential of a cell rapidly rises and falls
-so electrical current travels down an axon of a neuron

14

acetylcholine

a chemical compound that acts as a neurotransmitter and delivers the message for contraction

15

what is resting membrane potential

-70 mV (maintained by ATP pump)

16

depolarization

-rising membrane potential
-sodium ion channels open allowing sodium to flow into the cell
-becomes more positive

17

repolarization

-decreasing membrane potential (after hitting 33 mV)
-positively charged K ions flow out of the cell
-becomes more negative
-results in hyperpolarization

18

hyperpolarization

-more negative membrane potential (-90 mV)
-regaining resting membrane potential after repolarization

19

what % is actin and myosin bound in normal muscle

20% bound together
80% not bound together

20

what % is actin and myosin bound together post mortem (no ATP produced)

100% actin and myosin bound together (forms actomyosin)

21

actomyosin

complex protein forms by the cross bridge of actin and ,myosin

22

red muscle fiber

-more myoglobin content
-tonic (locomotive)
-slow contractions
-not easily fatigued
-distance runner
-smaller
-high capillary density (2:1)

23

white muscle fiber

-less myoglobin content
-phasic (supportive)
-fast contractions
-easily fatigued
-sprinter
-larger
-low capillary density (1:1)

24

why do muscles burn when exercising

-not enough oxygen delivered to muscles
-leads to breakdown of glycogen into lactic acid

25

how can a marathon runner get more energy production and high endurance

-oxidative metabolism
-more mitochondria
-more myoglobin
-smaller diameter so that and waste dissipate faster
-more lipid for energy storage

26

red vs. white muscle in face

eyes = white (rapid blink)
lips = red (long chewing)

27

epimysium

-surrounds muscle
-prevents friction

28

perimysium

-surrounds muscle bundles

29

endomysium

-surround the individual muscle fibers in the muscle bundle

30

order of muscle makeup from smallest to largest

-muscle
-muscle bundle
-muscle fiber
-myofibril
-myofilament (actin + myosin)