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.
Didn't know it?
click below
Knew it?
click below
Don't know
Remaining cards (0)
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

chapter 6 muscles

contractility the ability of skeletal muscle to shorten with force
elasticity ability to recoil to their original resting length after they have been stretched
extensibility the ability to be stretched
excitability the capacity of skeletal muscle to respond to a stimulus
What does an I band consist of? actin
tetany where the muscle remains contracted without relaxing
Where is ATP produced? mitochondria
Fast-twitch fibers... contract quickly and fatigue quickly
Slow-twitch fibers... contract more slowly and are more resistant to fatigue
Muscles that work together to accomplish specific movements are called... synergists
Muscles that work in opposition to one another are called... antagonists
Flexor carpi flexes the wrist
Extensor carpi extends the wrist
Flexor digitorum flexes the fingers
Extensor digitorum extends the fingers
Triceps brachii extends the forearm; occupies the posterior component of the arm
Biceps brachii flexes the forearm; occupies the anterior component of the arm
Brachialis flexes forearm
Brachioradialis flexes and supinates the forearm
Trapezius rotates scapula
Serratus anterior pulls scapula anteriorly
Pectoralis major adducts and flexes the arm
Lastissimus dorsi medially rotates, adducts, and powerfully extends the arm. "swimmer muscles"
Deltoid attaches the humerus to the scapula and clavicle, and is the major abductor of the upper limb
Occipitofrontalis raises the eyebrows
Orbicularis oculi closes the eyelids and causes "crows feet" wrinkles in the skin at the lateral corners of the eye
Orbicularis oris puckers the lips
Buccinator flattens the cheeks; trumpeter's muscles
Zygomaticus smiling muscle
Levator labii superioris sneering
Depressor anguli oris frowning
Mastication chewing
Each skeletal muscle is surrounded by a connective tissue sheath called the... epimysium
What is another connective tissue located outside the epimysium that surrounds and separates muscles? fascia
A muscle is composed of numerous visible bundles called what? muscle fasciculi (fascicle)
Muscle fasciculi are surrounded by loose connective tissue called the what ? perimysium
The fasciculi are composed of single muscle cells called what? Muscle fibers
Each fiber is surrounded by a connective tissue sheath called the what? endomysium
The cytoplasm of each muscle fiber is filled with what? myofibrils
What are myofibrils? a threadlike structure that extends from one end of the fiber to the other
2 major kinds of protein fibers actin and myosin
gluteus maximus buttocks
quadriceps femoris extends the leg; anterior thigh muscles
sartorius "tailors muscle"; flexes the thigh
hamstring muscles posterior thigh muscles; flexes the leg and extends the thigh
intrinsic foot muscles 20 muscles that flex, extend, abduct, and adduct the toes
peroneus lateral muscles of the leg; everters of the foot and aid in plantar flexion
gastrocnemius and soleus form the calf muscle; form the calcaneal tendon, flex the foot and toes
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
intrinsic hand muscles 19 hand muscles
interossi muscles located between the metacarpals, are responsible for the abduction and adduction of the fingers
gluteus medius hip muscle and common injection site
diaphragm accomplishes quiet breathing, dome-shaped muscle
erector spinae group of muscles on each side of the back, responsible for keeping the back straight and the body erect
sternocleidomastoid lateral neck muscle and prime mover, rotates and abducts the head
thoracic muscles muscles that move the thorax
external intercostals elevate the ribs during inspiration
internal intercostals contract during forced expiration
linea alba a vertical linear indentation is visible, extending from the sternum, through the navel to the pubis; consists of white connective tissue rather than muscle
rectus abdominis muscles on each side of the linea alba
tendinous inscriptions cross the rectus abdominis at three or more locations, causing the abdominal wall of a well-muscled person to appear segmented
The time of contraction is the... contraction phase
The time during which the muscle relaxes is the... relaxation phase
The increase in number of motor units being activated is called... recruitment
Anaerobic respiration without oxygen
Aerobic respiration with oxygen
Origin the most stationary end of the muscle
The portion of the muscle between the origin and the insertion is... belly
Among a group of synergists, if one muscle plays the major role in accomplishing the desired movement, it is the... prime mover
The end of the muscle undergoing the greatest muscle is... insertion
isometric the length of the muscle does not change, but the amount of tension increases during the contraction process
isotonic the amount of tension produced by the muscle is constant during contraction, but the length of the muscle changes
oxygen debt the amount of oxygen needed in chemical reactions to convert lactic acid to glucose and to replenish the depleted stores of creatine phosphate stores in muscle cells
The time between application of a stimulus to a motor neuron and the beginning of a contraction is the... lag phase
A muscle fiber will not respond to stimulus until that stimulus reaches a level called... threshold
The sliding of actin myofilaments past myosin myofilaments during contraction is called the... sliding filament mechanism
Created by: lexieleonard



Use these flashcards to help memorize information. Look at the large card and try to recall what is on the other side. Then click the card to flip it. If you knew the answer, click the green Know box. Otherwise, click the red Don't know box.

When you've placed seven or more cards in the Don't know box, click "retry" to try those cards again.

If you've accidentally put the card in the wrong box, just click on the card to take it out of the box.

You can also use your keyboard to move the cards as follows:

If you are logged in to your account, this website will remember which cards you know and don't know so that they are in the same box the next time you log in.

When you need a break, try one of the other activities listed below the flashcards like Matching, Snowman, or Hungry Bug. Although it may feel like you're playing a game, your brain is still making more connections with the information to help you out.

To see how well you know the information, try the Quiz or Test activity.

Pass complete!

"Know" box contains:
Time elapsed:
restart all cards