Busy. Please wait.

show password
Forgot Password?

Don't have an account?  Sign up 

Username is available taken
show password


Make sure to remember your password. If you forget it there is no way for StudyStack to send you a reset link. You would need to create a new account.
We do not share your email address with others. It is only used to allow you to reset your password. For details read our Privacy Policy and Terms of Service.

Already a StudyStack user? Log In

Reset Password
Enter the associated with your account, and we'll email you a link to reset your password.
Don't know
remaining cards
To flip the current card, click it or press the Spacebar key.  To move the current card to one of the three colored boxes, click on the box.  You may also press the UP ARROW key to move the card to the "Know" box, the DOWN ARROW key to move the card to the "Don't know" box, or the RIGHT ARROW key to move the card to the Remaining box.  You may also click on the card displayed in any of the three boxes to bring that card back to the center.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.

  Normal Size     Small Size show me how

Muscle System

Ch. 6 flashcards

contractibility shorten with force
excitability respond to a stimulus
extensibility ability to be stretched
elasticity recoil to original resting length after being stretched
epimysium skeletal muscle surrounded by connective tissue sheath
fascia connective tissue outside epimysium. surrounds and separates muscle
perimysium muscle composed of numerous visible bundles called muscle fasciculi, surrounded by loose connective tissue
fibers fasciculi composed of single muscle cells
endomysium surrounded by connective sheath
myofibrils threadlike structure that extends from one fiber to the other
actin myofilaments thin myofilaments
myosin myofilaments thick myofilaments
sarcomeres actin and myosin myofilaments join end to end to form myofibril
resting membrane potential charge difference across the membrane
action potential brief reversal back of the charge
motor neurons nerve cells that carry action potentials to skeletal muscle fibers
neuromuscular junction each branch that connects to the muscle near the center of the cell
synapse branch that connects to the muscle near the center of the cell
motor unit single motor neuron and all the skeletal muscle fibers it innervates
presynaptic terminal enlarged nerve terminal
synaptic terminal space between the presynaptic terminal and muscle cell
postsynaptic terminal muscle fiber
synaptic cleft space between the presynaptic terminal and muscle cell
synaptic vesicles presynaptic terminal
acetylcholine secrete a neurotransmitter
acetylcholinesterase acetylcholine released into synaptic cleft between the muscle and neuron and muscle cell, rapidly broken down by enzymes
sliding filament mechanism sliding of actin myofilaments past myosin myofilaments during contraction
muscle twitch contraction of an entire muscle in response to a stimulus that causes action potential in one or more muscle fibers
threshold muscle fiber will not respond to stimulus until that stimulus reaches a level
all-or-none response the muscle fiber will contract maximally
lag phase time between application of a stimulus to a motor neuron and the beginning of a contraction
contraction phase time of contraction
relaxation phase time which the muscle relaxes
tetany where muscles remain contracted without relaxing
recruitment increase in number of motor units being activated
creatine phosphate when at rest they cant stockpile ATP but they can store another high energy molecule
anaerobic respiration without oxygen
aerobic respiration with oxygen
oxygen debt the amount of oxygen needed in chemical reactions to convert lactic acid to glucose, replenish depleted phosphate in muscle cells
muscle fatigue results when ATP is used during muscle contraction faster than it can be produced in muscle cells
isometric length of the muscle does not change, but the amount of tension increases during the contraction process
muscle tone constant tension produced by muscles of the body for long periods of time
fast-twitch fibers contract quickly and fatigue quickly. well adapted to perform anaerobic metabolism
slow- twitch fibers contract more slowly and are more resistant to fatigue
origin most stationary end of the muscle
insertion end of the muscle undergoing the greatest movement
belly portion of the muscle between the origin and the insertion
synergists muscles that work together to accomplish specific movement
antagonists muscles that work in opposition to one another
prime mover if one muscle plays the major role in accomplishing the desired movement
mastication chewing
sternocleidomastoid lateral neck muscle and prime mover
erector spinae group of muscles on each side of the back
thoracic muscles muscles that move the thorax
abdominal wall muscles muscles of the anterior abdominal wall flex and rotate the vertebral column
trapezius rotates scapula
serratus anterior pulls scapula anteriorly
pectorals major adducts and flexes the arm
latissimus dorsi medially rotates, adducts, an powerfully extends the arm
deltoid attaches the humerus to the scapula and clavicle, abductor of the upper limb
Triceps brachii Extends the forearm
Biceps brachii Flexes the forearm
Brachialis flexes forearm
brachioradialis flexes and supinates the forearm
retinaculum strong band of fibrous connective tissue that covers the flexor and extensor tendons and holds them in place around the wrist so that they do not "bowstring" during muscle contraction
flexor carpi flexes the wrist
extensor carpi extends the wrist
flexor digitorum flexes the fingers
extensor digitorum extends the fingers
gluteus Maximus buttocks
quadriceps femoris extends the leg; anterior muscles
Sartorius "tailors muscle" ; flexes the thigh
hamstring muscles posterior thigh muscles; flexes the leg and extends the thigh
gastrocnemius and soleus form the calf muscle
calcaneal tendon (Achilles tendon) flex the foot and toes
intrinsic foot 20 muscles located within the foot, muscles flex extend, abduct, and adduct the toes
Created by: kirissa