Chapter 10 Muscle Phisiology

Question 1

Muscle cells (fibers) are

Answer 1

-contractile- get shorter
-extensible- get longer
-elastic- return to normal shape after getting shorter/longer

-excitable-can create and carry electrochemical signais
(Sliding filament Theory)

Question 2

Endomysium

Answer 2

Surrounds muscle cell

Question 3

Transverse (T) -tubule is

Answer 3

inward Projections of cell membrane (sarcol emma) that go through in a transverse direction through cell

Question 4

Sarcoplasmic reticulum

Answer 4

stores a releases ca+ ions (specialized ER)

Question 5

Myofibrils are

Answer 5

Little fiber inside muscle cell

Question 6

Triad is

Answer 6

Terminal cisternae on each side of the T-tubule

Question 7

Order of muscle cell

Answer 7

Myofilaments are inside myofibrils→ inside muscle fibers (cells) → inside the muscle fascicles → inside muscle (organ)

Question 8

Thick filament is

Answer 8

Myosin (head)

Question 9

Thin filaments are

-consists of

Answer 9

Actins

-tropomyosin
-troponin

Question 10

Tropomyosin is

Answer 10

(Rope) Strings along actin and covers the active sites

Question 11

Troponin is

Answer 11

Proteins scattered across tropomyosin
(Moves protein)

Question 12

Sarcomere

Answer 12

functional unit of skeletal muscle contraction

Question 13

•When we establish a RMP
-90 mv) we say the cm is

Answer 13

Polarized

Question 14

when the Na+ is rushing in the cmis

Answer 14

Depolarized

Question 15

Myographs

Answer 15

Generates recordings of a muscle twitch

Question 16

•muscle twitch (single twitch)

Answer 16

response of muscle fiber to a single action Potential in a motor neuron
(Spits out 1 ACh)

Question 17

•unfused tetanus

Answer 17

muscle fiber Not allowed to relax complety between stimuli
(spits out mult. Ach fast; like 30-50 times per min)

Question 18

Fused tetanus

Answer 18

muscle fibers NoT allowed to relax between stimuli
-tension remains constant at maximal level
-Spits Ach out about 40-60 times/min

TENSION HIGHEST HERE

Question 19

when Ach is no longer being spat out what happens

Answer 19

Muscle relaxes

Question 20

If skeletal muscle cells follow the “All or Nothing Principle”.
…How do we create varying
amounts of force?

Answer 20

we decide how many cells to use to create force we need

Question 21

Motor unit

Answer 21

1 motor neuron and the muscle fibers it’s controls ( spits out)

-some motor units are as small as 2to 3 muscle fibers

AVERAGE SIZE IN HUMANS- 150 muscle cells per motor unit

Question 22

Differential recruitment

Answer 22

usin different numbers of motor units for Particular actions

-small effort =fewer motor units
- recruiting all motor units =greatest force generated

Question 23

Isotonic contraction is

Answer 23

Tension- constant
Length -changes

Question 24

Isometric contraction

Answer 24

Length is constant (no change)

Tension changes

Question 25

Isotonic CONCENTRIC contraction

Answer 25

Muscle shortens (regular contraction)

Question 26

Isotonic ECCENTRIC contraction

Answer 26

Muscle gets longer while contracting

Question 27

Where do cells get ATP

Answer 27

They make it

Question 28

2molecules that help (a little bit) with ATP. Production

Answer 28

1: myoglobin

2: creatine PhosPhate

Question 29

Myoglobin

Answer 29

Provides little more 02 (for more aerobic metabolism) (Red)

Question 30

creatine PhosPhate

Answer 30

can provide extra Phosphates for ATP Production for about 10-15 secs.

Question 31

To get muscles larger & Stronger - you have to

Answer 31

Increase diameter of muscle fibers

(Makes cells we have bigger doesn’t create new cells)

Question 32

Oxygen debt is

Answer 32

the 02 needed to restore pre-work conditions to a muscle

Question 33

If ATP’S run out in a muscle what happens?

Answer 33

The muscle stays how it was when the ATP ran out because the myosin heads can’t release because their is no more ATP

-this causes rigor morris

Question 34

smooth muscle fibers binds different than skeletal muscle in that

Answer 34

Calcium Ca+ - binds too calmodulin (not troponin)

-calmodulin actives enzyme —> myasin light chain kinase ( allows myosin to attach to actins)

Question 35

Smooth muscles still
BUT do what differently than skeletal muscles

Answer 35

Contract and move

Have myosin’s and actins

Have different arrangement of myofilaments

Question 36

•atrophy means

Answer 36

decrease in size of cell due to lose of myofibrils

Question 37

hypertrophy means

Answer 37

increase in cell size, increase number of myofibrils and diameter of muscle cells

Question 38

Lactic acid is

Answer 38

Muscles and red blood cells produce lactic acid when body breaks down glucose and there isn’t enough oxygen to create its normal energy

Question 39

Myasthenia Gravis

Answer 39

Weakness and rapid fatigue of muscles under voluntary control

Question 40

Tendinitis is

Answer 40

Inflammation of a tendon from injury or overuse of

Question 41

Duchenne muscuar dystrophy is

Answer 41

Inherited disorder of progressive muscular weakness
-typically in boys

Question 42

Duchenne muscuar dystrophy is

Answer 42

Inherited disorder of progressive muscular weakness
-typically in boys

Question 43

aponeurosis means

Answer 43

a thin sheath of connective tissue that helps connect your muscles to your bones.

Question 44

fixator means

Answer 44

a muscle that stabilizes or fixes a part of the body to which a muscle in the process of moving another part is attached.