Muscular System Flashcards
The ability of a muscle cell to shorten in length is called
Contractility
The ability to received and respond to stimulus is
Excitability
The ability of a muscle cell to stretch is
Extensibility
The ability of a cell to return to its resting form after stretching is called
Elasticity
The type of muscle tissue found in the muscular system is
Skeletal Muscle Tissue
The connective tissue that binds a muscle and provides a route for blood vessels and nerves to travel is called
Deep Fascia
The type of fascia that surrounds a muscle is called
Deep Fascia
The outermost covering of the entire muscle is the _____ which is deep fascia
Epimysium
A thick band of dense connective tissue that forms most connections between muscle and bone is called a
Tendon
A broad sheet of dense connective tissue that may attach a muscle to a bone or to another muscle is
Aponeurosis
A tendon rupture is a serious injury calling for _____ to reconnect the torn ends
Surgery
Overuse of a tendon, called _____ results in pain and inflammation
Tendonitis
A single cell of skeletal muscle tissue is called a
Muscle Fiber
The plasma membrane of a muscle cell is called a
Sarcolemma
The cytoplasm of a muscle cell is called
Sarcoplasm
Most of the energy for the contraction of a muscle cell is furnished by the ATP of the
Mitochondria
Calcium storage occurs at the _____ which is similar to the endoplasmic reticulum of other cells
Sarcoplasmic reticulum
Between adjacent sarcoplasmic reticular sacs is a tube called the _____ which unites with the sarcolemma
Transverse (T) tubule
_____ are tiny parallel fibers which extend the length of a muscle fiber
Myofibrils
There are two types of protein filaments in myofibrils: _____ and ______
Thin filaments and thick filaments
Thick filaments are composed of _____
Myosin
Thin filaments are composed of _____, troponin and tropomyosin
Actin
The striations seen on a muscle cell are made of dark bands called _____ and light bands called _____
A bands; I bands
The segment of myofibril between two Z lines is called a _____S
Sarcomere
The difference in charges (+ outside and - inside) across a plasma membrane causes a small voltage difference which is called
Resting membrane potential
The end of a motor neuron, a motor end place, and the narrow space in between is referred to as the
Neuromuscular Junction
Acetylcholine is located in tiny sacs called ____ which are located at the terminal end of motor neurons
Synaptic Vesicles
When a nerve or muscle cell is stimulated, there is a brief reversal of charges across the cell membrane. This reversal is called an
Action potential
The functional unit consisting of a single motor neuron and the many muscle fibers it stimulates is called a
Motor unit
______ is a term for a chemical that carries a signal from one nerve end to either another neuron or to a muscle cell
Neurotransmitter
ACh is an abbreviation for
Acetylcholine
For at rest muscle fibers, ATP is chemically attached to _____
Myosin proteins
For at rest muscle fibers, the thin filaments are ready with ____, _____ and _____
Actin, Troponin and Tropomyosin
What is the chemical stimulus that begins a muscle contraction
Acetylcholine release
What is the sequence of muscle contraction
- Calcium binds to troponin molecules reshaping the actin and troponin molecules
- Connections are made between thin and thick filaments
- Calcium (with the catalyzing action of myosin) causes the release of potassium and energy from ATP molecules
- Energy released in the breakdown of ATP increases body temperature (which is why the body becomes warm during exercise)
Simplified sequence of muscle contraction
- Cross bridge formation
- Cross bridge movement
- Cross bridge release
- Z lines of the sarcomere are shortened as they are drawn together
Rigor mortis can best be described as
Muscular rigidity due to unreleased cross bridges in the muscle cells
What biochemical change is most directly responsible for the return of a muscle fiber to a resting condition
Absence of calcium ions
What are examples of direct use of the energy from ATP breakdown
The mechanical movement of cross bridges
The breakage of cross bridge attachments from thin filaments
The return of calcium to the sarcoplasmic reticulum
What does soreness after exercise come from?
Lactic acid accumulation
T/F: In muscles that are exercised strenuously for a prolonged period of time, the oxygen debt may lead to muscle fatigue
True
T/F: Muscle fatigue is the inability of a muscle to contract normally
True
When a muscle contracts in a spasm without relaxing, the result is
A cramp
As the diameter of a muscle fiber increases, the strength of contraction
Increases
Where is skeletal muscle found
Attached to skeleton
How is skeletal muscle controlled
Voluntary
What is skeletal muscle’s shape
Long, cylindrical
Are there striations in skeletal muscle
Present
Order of contraction speed race for skeletal muscle
Fastest
Order of contraction strength for skeletal muscle
Strongest
Order of contraction time for skeletal muscle
Least
Where is smooth muscle found
In walls of hollow organs
How is smooth muscle controlled
Involuntary
How is cardiac muscle controlled
Involuntary
Where is cardiac muscle found
In walls of heart
Smooth muscle shape
Spindle-shaped
Cardiac muscle shape
Cylindrical, branching
Are there striations in smooth muscle?
Absent
Are there striations in cardiac muscle?
Present
Order of contraction speed race for smooth muscle
Slowest
Order of contraction speed race for cardiac muscle
Medium
Order of contraction strength for smooth muscle
Weakest
Order of contraction strength for cardiac muscle
Medium
Order of contraction time for smooth muscle
Greatest
Order of contraction time for cardiac muscle
Intermediate
The weakest stimulus that can initiate a contraction
Threshold stimulus
A stimulus that is too weak to cause a contraction
Subthreshold Stimulus
The complete contraction of a muscle fiber in response to a stimulus above the minimum amount
All-or-none response
Addition of motor units as stimulus strength increases
Recruitment
A rapid response to a single stimulus, a basic unit of muscle contraction
Twitch
A muscle warm up phenomenon in which single twitches rapidly follow each other
Treppe
A second, stronger contraction when a muscle receives a second stimulus before the first contraction cycle is complete
Wave summation
A continuous contraction due to a fusion of twitches
Complete tetanus
A type of tetanus in which only a small number of fibers contract affecting posture
Muscle tone
The usual means of producing body movement
Isotonic contraction
Muscle tension, without shortening the muscle
Isometric contraction
Learning a new coordination action
Motor Skill Development
Sustained muscular efforts with benefit to cardiovascular and respiratory systems
Endurance
The point of attachment to the more stationary bone
Origin
The point of attachment to the more movable bone
Insertion
The coordinated response of a group of muscles that causes a body movement
Group Action
Muscles in a group which cause the desired action
Prime Movers
The muscles in a group that relax during the action
Antagonists
The muscles in a group which steady the movement
Synergists
The muscles in a group which stabilize the origin of the prime mover
Fixators
Sphere of the eye
Orbicularis Oris
Sphere of the mouth
Orbicularis Oculi
Trumpeter
Buccinator
Cheek
Zygomaticus
One who chews
Masseter
Breast bone, clavicle, breast-resembling process
Sternocleidomastoid
Table-like
Trapezius
One who raises the shoulder-blade
Levator scapulae
Saw
Serratus
Of the breast, small
Pectoralis Minor
Triangular
Deltoid
Rounded
Teres
Three heads in the arm
Triceps Brachii
Two heads in the arm
Biceps Brachii
Vertical presence of the abdomen
Rectus Abdominis
Great presence of the buttocks
Gluteus Maximus
Slender
Gracilis
Tenses fascia on the lateral
Tensor fascia latae
Tailor
Sartorius
Four heads of the femur
Quadriceps Femoris
Stomach of the lower leg
Gastrocnemius
Sole of the foot
Soleus
RICE stands for
Rest Ice Compression Elevation
The kissing muscles are ______ and the _____
Orbicularis Oculi/Buccinator
Largest muscle of the group which connects the pectoral girdle to the thorax is the
Trapezius
The muscle commonly known as the “lat” is the
Latissimus Dorsi
Injections are commonly given in a muscle called the
Deltoid
A vertical line (a ridge of connective tissue) extending from the sternum to the navel is called the
Linea Alba
A muscle which is a common site for injections in the hip area is the
Gluteus Medius
The _____ muscles acquire their name from the butcher shop where their tendons were used to suspend pig meat during curing
hamstring
The gastrocnemius and the soles insert via a common heel tendon known as the
Achilles Tendon
