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

chapter 6 flashcards


The ability of skeletal muscle to shorten with force. Contractility
The capacity of skeletal muscle to respond to a stimulus. Excitability
The ability to be stretched. Extensibility
The ability to recoil to their original resting length after they have been stretched. Elasticity
They help to produce heat essential for maintenance of normal body temperature. Mescles
Each skeletal muscle is surrounded by a connective tissue sheath called... Epimysium
This is another connective tissue located outside the epimysium. It surrounds and separates muscles. Fascia
A muscle is composed of numerous visible bundles called... Muscle Fasciculi (fascicle)
Fascicle which are surrounded by loose connective tissue called... Perimysium
The fasciculi are composed of single muscle cells called... Fibers
Each fiber is surrounded by a connective tissue sheath called... Endomysium
The cytoplasm of each fiber is filled with... Myofibrils
A threadlike structure that extends from one end of the fiber to the other. Myofibrils
What are the four major functional characteristics of the skeletal muscle? Contractility, Excitability, Extensibility, and Elasticity
Myofibrils consist of 2 major kinds of protein fibers... Actin Myofilaments, and Myosin Myofilaments
Thin myofilaments Actin Myofilaments
Thick myofilaments Myosin Myofilaments
They resemble 2 minute strands of pearls twisted together. Actin
They resemble bundles of minute golf clubs. Myosin
Actin and myosin myofilaments form highly ordered units called... Sarcomeres
Sarcomeres Which are joined end to end to form the myofibril.
The arrangement of actin and myosin give... Banded appearance
On each side of the Z line is a light area called... I band
The A band extends the length of the... Myosin
In each sarcomere... The center region is darker.
In the center of each sarcomere is another light area called... H zone
The myosin myofilaments are anchored in center of the sarcomere at a dark staining band called... M line
The outside of most cell membranes is positively charged compared to the inside of... Cell membrane
The charged difference across the membrane is called... Resting Membrane Potential
When a muscle cell is stimulated the membrane characteristics... Change briefly
The brief reversal back of the charge is called... Action Potential
Nerve calls that carry action potentials to skeletal muscle fibers. Motor Neurons
Axons enter... The muscles and branch.
Each branch that connects to the muscle forms a... Neuromuscular Junction
Near the center of the cell. Synapse
A single motor neuron and all the skeletal muscle fibers it innervates are called... Motor Unit
Many motor unit form... Single muscle
A neuromuscular junction is formed by an enlarged nerve terminal resting in an indentation of the... Muscle cell membrane
The enlarged nerve terminal is the... Presynaptic terminal
The space between the presynaptic terminal and the muscle cell is the... Synaptic cleft
The muscle fiber is... Postsynaptic terminal
Each presynaptic terminal contains... Synaptic vesicles
Synaptic vesicles that secrete a neurotransmitter called... Acetylcholine
The diffuses across the synaptic cleft and binds to the postsynaptic terminal causing a changed in the... Postsynaptic cell
When an action potential reaches the nerve terminal, is causes... synaptic vesicles to release acetylcholine into synaptic cleft and exocytosis.
The acetylcholine diffuses across the synaptic and binds to receptor molecules in the... Sarcolemma
The combination of acetylcholine with its receptor causes... An influx of sodium ions into the muscle fiber.
The influx initiates an action potential in the... Muscle cell
The acetylcholine released into the synaptic cleft between the neuron and muscle cell is rapidly broken down by an enzymes... Acetylcholinesterase
Occurs as actin and myosin myofilaments slide past one another causing... Sarcomeres to shorten
When the sarcomeres shorten it causes the muscles to... Shorten
The sliding of actin myofilaments past myosin myofilaments during contraction is called... Sliding filament mechanism of muscle contraction.
Bands that do not change length... A bands
Bands that shorten... H and I bands
Is a contraction of an entire muscle in response to a stimulus that causes the action potential in one or more muscle fibers. Muscle twitch
A muscle fiber will not respond to stimulus until that stimulus reaches a level called... Threshold
This phenomenon is called... All-or-none response
The time between application of a stimulus to a motor neuron and beginning of a contraction is the... Leg phase
The time of contraction is the... Contraction phase
The time during which the muscle relaxes is the... Relaxation phase
If successive stimuli are given you get successive twitches that occur so frequently the muscle doesn't have time to... Fully relax
Where the muscle remains contracted without relaxing. Tetany
The increase in number of motor units being activated is called... Recruitment
When at rest they can't stockpile ATP but they can store another high-energy molecule, called... Creatine phosphate
Without oxygen Anaerobic respiration
With oxygen Aerobic respiration
Results when ATP is used during muscle contraction faster than it can be produced in the muscle cells. Muscle fatigue
2 types of muscle contractions. Isometric, and Isotonic
Equal distance this length of the muscle does not change, but the amount of tension increases during contraction process. Isometric
Equal tension the amount of produced by the muscle is constant during contraction, but the length of the muscle changes. Isotonic
Refers to constant tension produced by muscles of the body for long periods of time. Muscle tone
Contract quickly and fatigue quickly. Fast-twitched fibers
Contract more slowly and are more resistant to fatigue. Slow-twitch fibers
Is the most stationary end of the muscle. Origin (head)
Is the end of the muscle underdog the greatest movement. Insertion
The portion of the muscle between the origin and the insertion is the... Belly
Muscles that work together to accomplish specific movements are called... Synergists
Muscles that work in opposition to one another are called... Antagonists
Created by: chlogirlisfab99