Busy. Please wait.
or

show password
Forgot Password?

Don't have an account?  Sign up 
or

Username is available taken
show password

why


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
Know
remaining cards
Save
0:01
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:
Retries:
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 Anatomy

muscles

QuestionAnswer
Contractility the ability of the skeletal muscle to shorten with force
excitability the capacity of skeletal muscle to respond to a stimulus
extensibility the ability to be stretched
elasticity ability to recoil to their original resting length after they have been stretched
each muscle is surrounded by a connective tissue sheath called what the epimysium
another connective tissue located outside the epimysium that surround and separates muscles facsia
a muscle is composed of of numerous visible bundles called what muscle fasciculi
Muscle fasciculi are surrounded by loose connective tissue called the perimysium
the fasciculi are composed of single muscle cells called fibers
T or F? Each muscle fiber is a single cylindrical cell containing several nuclei. True
each fiber is surrounded by a connective tissue sheath called the endomysium
the cytoplasm of each fiber is filled with myofibrils
define myofibrils a thread like structure that extends from one end of the fiber to the other.
Myofibrils consist of two major kinds of protein fibers which are actin and myosin microfilaments
define actin microfilaments thin myofilaments
define myosin microfilaments thick myofilaments
actin and myosin myofilaments form highly ordered units called sarcomeres
sarcomeres are joined end to end to form the myofibril
basic structural and functional unit of the muscle sarcomeres
the H zone consists only of myosin
The charge difference across the membrane is called the resting membrane potential
the brief reversal back of the charge is called action potential
nerve cells that carry action potentials to skeletal muscle fibers motor nuerons
each branch that connects to the muscle forms a ______ near the center of the cell neuromuscular junction, or synapse
a single motor neuron and all the skeletal muscle fibers it innervates are called a motor unit
many motor units form a single muscle
formed by an enlarged nerve terminal resting in an indentation of the muscle cell membrane a neuromuscular junction
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 the postsynaptic terminal
each presynaptic terminal contains synaptic vesicles
synaptic vesicles secrete a neurotransmitter called acetylcholine
diffuses across the synaptic cleft and binds to the postsynaptic terminal causing a change in the postsynaptic cell acetylcholine
acetylcholine releases into the cynaptic cleft between the neuron and muscle cell is rapidly broken down by acetylcholineesterase
the sliding of actin myofilaments past myosin myofilaments during contaction is called the sliding filament mechanism of muscle contraction
a contraction of an entire muscle in response to a stimulus the causes the action potential in one or more muscle fibers muscle twitch
point at which the muscle fiber will contract maximilly threshold
time between application of a stimulus to a motor neuron and the beginning of a contraction is the lag phase
the time of contraction is the contraction phase
the time during the muscle relaxes is called the relaxation phase
the muscle remains contracted without relaxing tetany
the increase in number of motor units being activated is called recruitment
ATP adenosine triphosphate
atp is needed for energy for muscle contaction
atp is produced in the mitochondria
anaerobic respiration without oxygen
aerobic with oxygen
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
muscle fatigue results when ATP is used during muscle contraction faster than it can be produced in the muscle cells
2 types of muscle contraction isometric and isotonic
muscle refers to constant tension produced by muscles of the body for long periods of time
contract quickly and fatigues quickly fast-twitch fibers
contract more slowly and are more resistant to fatigue slow-twitch fibers
the most stationary end of the muscle origin (head)
the end of a muscle undergoing the greatest movement insertion
portion of the muscle between the origin and the insertion the belly
synergists muscles that work together to accomplish specific movements
muscles that work in opposition to one another are called antogonists
occipitofrontalis raises the eyebrows
orbicularis oculi closes the eyelids and causes "crow's feet"
orbicularis oris puckers the lips
buccinator flattens the cheeks
zygomaticus smiling muscle
levator labii superioris sneering
depressor anguli oris frowning
mastication means chewing
4 pairs of mastication muscles 2 pair of pterygoids, temporalis, and masseter
intrinsic tongue muscles change the shape of the tongue
extrinsic tongue muscles move the tongue
sternocleidomastoid lateral neck muscle and prime mover. rotates and abducts the head
erector spinae group of muscles on each side of the back
flexor carpi flexes the wrist
extensor carpi extends the wrist
flexor digitorium flexes the fingers
extensor digitorium extends the fingers
Created by: samantharuthann