Muscles

Question 1

functions of muscular system

Answer 1

• movement
• maintain posture
• support tissue
• maintain body temp
• guard entrances
• store nutrients

Question 2

sarcolemma

Answer 2

plasma membrane

Question 3

sarcoplasm

Answer 3

cytoplasm

Question 4

myofibrils

Answer 4

bundles of actin and myosin that fill sarcoplasm

Question 5

sarcomere

Answer 5

functional unit of myofibril between two z lines

Question 6

a bands

Answer 6

dark stripes, myosin

Question 7

I bands

Answer 7

thin light stripes, actin

Question 8

function of t-tubules

Answer 8

allow electrical impulses to travel deep into cell

Question 9

2 myofilaments that prevent binding of actin and myosin

Answer 9

tropomyosin

troponin

Question 10

muscle fascicle

Answer 10

bundle of muscle fibers

Question 11

endomysium

Answer 11

surrounds each individual muscle fiber

Question 12

perimysium

Answer 12

surrounds muscle fascicle

Question 13

epimysium

Answer 13

surrounds entire muscle

Question 14

layers of the muscle including connective tissue sheaths

Answer 14

myofilaments
myofibrils
muscle fiber
endomysium
muscle fascicles
perimysium
muscle
epimysium

Question 15

neuromuscular junction

Answer 15

where a nerve and muscle fiber meet

Question 16

motor end plate

Answer 16

area on sarcolemma where neuron sends signals

Question 17

synaptic cleft

Answer 17

space between neuron and muscle fiber

Question 18

synaptic vesicles

Answer 18

store neurotransmitters inside neuron

Question 19

function of acetylcholine

Answer 19

induces electrical impulse hat spreads over the sarcolemma, causing the release of calcium ions

Question 20

function of sarcoplasmic reticulum

Answer 20

stores/ releases calcium ions

Question 21

function of calcium ions

Answer 21

bind to troponin, causing it and tropomyosin to release from myosin strands

Question 22

creatinine phosphate

Answer 22

converts ADP into ATP

Question 23

hemoglobin function

Answer 23

supplies muscles with oxygen

Question 24

myoglobin function

Answer 24

stores oxygen in muscle

Question 25

red fibers contain

Answer 25

lots of myoglobin

Question 26

white fibers contain

Answer 26

little myoglobin

Question 27

threshold stimulus

Answer 27

minimal impulse strength required to cause a contraction

Question 28

motor unit

Answer 28

muscle fiber and motor neuron together

Question 29

hypertrophy

Answer 29

muscle enlargement

Question 30

fatigue

Answer 30

loss of ability to contract after prolonged use

Question 31

cramp

Answer 31

sustained involuntary contraction

Question 32

steps of muscle movement

Answer 32

1. motor neuron sends acetylcholine to sarcolemma, causing impulse
2. impulse causes calcium to be released from sarcoplasmic reticulum
3. calcium binds to troponin, allowing actin and myosin to interact
4. ATP is used to create a “power stroke”
5. actin filament slides inward, shortening the sarcomere and contracting the muscle

Question 33

isotonic

Answer 33

tension is kept constant

Question 34

isometric

Answer 34

length is kept conatant

Question 35

isokinetic

Answer 35

energy is kept constant

Question 36

fast twitch diameter, mitochondria #, vascularity, and red/white

Answer 36

large diameter, few mitochondria, little vascular, mostly white mucle

Question 37

slow twitch diameter, mitochondria #, vascularity, red/white

Answer 37

small diameter, many mitochondria, lots of vascular tissue, red

Question 38

what causes rigor mortis

Answer 38

the body uses up all the oxygen so no more atp can be made

Question 39

first class lever

Answer 39

load and force are on opposite on opposite sides of fulcrum

ex: joint between head and vert.

Question 40

second class levers

Answer 40

load is between applied force and fulcrum

ex: standing on tiptoe

Question 41

third class levers

Answer 41

force is applied between load and fulcrum

ex: elbow joint