muscle physiology

Question 1

3 muscle types

Answer 1

skeletal, cardiac, smooth

Question 2

skeletal muscle

Answer 2

most abundant type (700+), functions: movement of skeleton, posture, supports soft tissue, guards entrances and exits, maintains body temp

Question 3

myofibril

Answer 3

protein bundle inside of a muscle cell

Question 4

muscle fiber

Answer 4

one cell

Question 5

fascicle

Answer 5

bundle of cells

Question 6

a bunch of fascicles

Answer 6

skeletal muscle (organ)

Question 7

tendons

Answer 7

attach muscle to bone

Question 8

length of skeletal muscle cell

Answer 8

can be up to 24 inches

Question 9

sarcomere

Answer 9

1 functioning unit of muscle cell

Question 10

myosin

Answer 10

thick filaments in sarcomere
has head and tail
many myosin proteins make up thick filament

Question 11

actin

Answer 11

thin filaments in sarcomere

Question 12

z line

Answer 12

boundary of sarcomere

Question 13

A band

Answer 13

area where thick filaments exist

Question 14

I band

Answer 14

area where thin filaments exist

Question 15

m line

Answer 15

center of sarcomere

Question 16

striations are the result of

Answer 16

actin and myosin

Question 17

muscle contractions are the result of

Answer 17

interactions between actin and myosin

Question 18

tropomyosin

Answer 18

fibrous protein that wraps helically around actin

Question 19

troponin

Answer 19

calcium binding sites found on tropomyosin

Question 20

contraction

Answer 20

thousands of myosin heads creating power strokes (see book for steps)

Question 21

rigor mortis

Answer 21

at death, run out of ATP. Ca leaks out of the sarcoplasmic reticulum and cross bridges form. without ATP the cross bridge can’t be broken. 15-25 hours later enzymes from lysosomes break myofilaments down

Question 22

tetanus

Answer 22

caused by Clostridium tetani, bacteria releases toxin that causes constant state of contraction. 40-60% mortality rate. aka lock jaw

Question 23

muscle tone

Answer 23

sarcomere is active during rest. no muscle contraction. stabilizes joints for posture and balance. varies per individual

Question 24

atrophy

Answer 24

muscles not stimulated on regular basis causes smaller and weaker cells (like from being in a cast)

Question 25

hypotonia

Answer 25

disease, decreased muscle tone

Question 26

creatine

Answer 26

used to turn ADP back into ATP for people trying to bulk up

Question 27

white muscle fibers

Answer 27

fast twitch, short fibers. make good sprinters

Question 28

red muscle fibers

Answer 28

slow twitch, long fibers. for distance running

Question 29

muscle cramps

Answer 29

caused by over exertion, low oxygen, salt, water, potassium, calcium

Question 30

muscular dystrophy

Answer 30

abnormalities in proteins of muscles causes muscle weakness and deterioration

Question 31

botox

Answer 31

injection of Clostridsium botulinum bacterial toxin paralyzes muscles in relaxed state so they cannot contract

Question 32

what’s wrong with micaela?

Answer 32

myasthenia gravis