Kin 2500 Exam 4
smooth
3 types of muscular tissue: ___________- is located in the walls of hollow internal structures, such as blood vessels, airways, and most organs in the abdominopelvic cavity. It is non-striated and involuntary, it is regulated by neurons that are part of the ANS (Autonomic Nervous System) and by hormones released by endocrine glands.
cardiac
3 types of muscular tissue: ___________- is only found in the heart, where it forms most of the heart wall. It is also striated, but its action is involuntary; its alternating contraction and relaxation cannot be consciously controlled. it is regulated by neurons that are part of the ANS (Autonomic Nervous System) and by hormones released by endocrine glands.
skeletal
3 types of muscular tissue: ___________- is so named because the function of most of these muscles is to move the bones of the skeleton. It is similar to cardiac muscle, it is striated because it has alternating dark and light protein bands which are visible when the tissue is examined under a microscope. It works primarily in a voluntary manner; its activity can be consciously controlled.
electromyography
Clinical Connection: __________________- is a test that measures the electrical activity (muscle action potentials) in resting and contracting muscles. Normally, resting muscle produces no electrical activity; a slight contraction produces some electrical activity; and a more forceful contraction produces increased electrical activity. The electrical activity of the muscle is detected by a recording needle placed on or in a muscle to be tested and displayed as waves on an oscilloscope and heard through a loudspeaker. (Blank) helps to determine whether muscle weakness or paralysis is due to a malfunction of the muscle itself or the nerves supplying the muscle. (Blank) is also used to diagnose certain muscle disorders, such as muscular dystrophy, and to understand which muscles function during complex movements.
sarcomere
Components of a Sarcomere: Z- disc comes closer together, the ______________ becomes shorter, but the length of the z discs doesn't change
H zone
Components of a Sarcomere: ___________- A narrow region in the center of each A band that contains thick filaments but no thin filaments
M line
Components of a Sarcomere: ___________- A region in the center of the H zone that contains proteins that hold the thick filaments together at the center of the sarcomere
Z discs
Components of a Sarcomere: ___________- Narrow, plate-shaped regions of dense protein material that separate one sarcomere from the next
A band
Components of a Sarcomere: ___________- The dark, middle part of the sarcomere that extends the entire length of the thick filaments and also includes those parts of the thin filaments that overlap with the thick filaments
I band
Components of a Sarcomere: ___________- The lighter, less dense area of the sarcomere that contains the rest of the thin filaments but no thick filaments. A Z disc passes through the center of each one.
fascicle (also called fasciculus)
Connective Tissue Coverings: Next, notice that groups of muscle fibers form bundles wrapped in a thicker layer of connective tissue. This muscle fiber bundle is a _________.
muscle belly
Connective Tissue Coverings: The ___________ is not just a large mass of individual muscle fibers, but groups of fibers wrapped in connective tissue. Even though we give the connective tissue layers three separate names, they form a continuous interconnected network.
endomysium
Connective Tissue Coverings: _______________- Invagination of the perimysium separating each individual muscle fiber (cell); Surrounding each muscle fiber is a thin wrapping of mostly reticular fibers called this. This surrounding connective tissue helps to bind the muscle fibers together, yet is loose enough to allow them to move freely over one another. It also carries small blood vessels that supply the fibers with nutrients.
epimysium
Connective Tissue Coverings: _______________- a fibrous connective tissue around muscles; Around the periphery of the muscle is a somewhat thicker covering of dense irregular connective tissue which binds all the fascicles together to form the muscle belly.
perimysium
Connective Tissue Coverings: _______________- invagination of the epimysium that divides muscles into bundles; the fascicles dense irregular connective tissue covering. It allows a certain degree of freedom of motion between neighboring fascicles and transmits blood vessels.
joint
Coordination Among Muscles: It is common to attribute a specific action at a _______ to a single muscle bundle, but remember that muscles do not work in isolation
synergist
Coordination Among Muscles: ____________- a muscle that assists the prime mover by reducing undesired action or unnecessary movement; prevent unwanted movements at intermediate joints or to otherwise aid the movement of the primer mover contract and stabilize the intermediate joints.
antagonist
Coordination Among Muscles: ____________- a muscle that has an action opposite that of the prime mover and yields to the movement of the prime mover; stretches and yields to the effects of the prime mover
fixator
Coordination Among Muscles: ____________- a muscle that stabilizes the origin of the prime move so that the prime mover can act more efficiently. They stabilize the origin of the prime mover so that the prime mover can act more efficiently. They steady the proximal end of a limb while movements occur at the distal end.
prime mover (agonist)
Coordination Among Muscles: ____________- the muscle directly responsible for producing a desired motion; contracts to cause an action
mesoderm
Development of Muscles: _______________- except for the muscle of the iris of the eyes, all muscles of the body are derived from this, the middle primary germ layer that gives rise to connective tissues, blood and blood vessels, and muscles.
somites
Development of Muscles: _______________- posterior to the developing head, the (blank) undergo further development into paired, cube-shaped structures called these which are blocks of mesodermal cells in developing embryo that is distinguished into a myotome (which forms most of the skeletal muscles), dermatome (which forms connective tissues), and sclerotome (which forms the vertebrae).
somitomeres
Development of Muscles: _______________- the paraxial mesoderm soon undergoes segmentation. Initially the segments form these, which are small bulges in the paraxial mesoderm.
parallel
Effects of Fascicle Arrangement: All muscle fibers are __________ to one another within a single fascicle. Fascicles, form patterns with respect to the tendons.
circular
Effects of Fascicle Arrangement: _________- fascicles in concentric circular arrangements form sphincter muscles that enclose an orifice. (Orbicularis oculi muscle)
fusiform
Effects of Fascicle Arrangement: _________- fascicles nearly parallel to longitudinal axis of muscle; terminate in flat tendons; muscle tapers toward tendons, where diameter is less than at belly (Digastric muscle)
parallel
Effects of Fascicle Arrangement: _________- fascicles parallel to longitudinal axis of muscle; terminate at either end in flat tendons (Sternohyoid muscle)
triangular
Effects of Fascicle Arrangement: _________- fascicles spread over broad area coverage at thick central tendon; gives muscle a triangular appearance
pennate
Effects of Fascicle Arrangement: _________- short fascicles in relation to total muscle length; tendon extends nearly entire length of muscle
bipennate
Effects of Fascicle Arrangement: Pennate- _________- fascicles are arranged on both sides of centrally positioned tendons (Rectus femoris muscle)
unipennate
Effects of Fascicle Arrangement: Pennate- _________- fascicles are arranged on only one side of tendon (Extensor digitorum longus muscle)
multipennate
Effects of Fascicle Arrangement: Pennate- _________- fascicles attach obliquely from many directions to several tendons (Deltoid muscle)
muscle tone
Even while at rest, a skeletal muscle exhibits ______________
sarcoplasm
Excitation-contraction coupling: 6. As long as muscle action potentials continue to propagate through the T tubules, the Ca2+ release channels remain open and Ca2+ flows into the _____________ faster than it is transported back into the SR by the Ca2+ active pumps.
calsequestrin
Excitation-contraction coupling: 7. After the last muscle action potential has propagated throughout the T tubules, the Ca2+ release channels close. As the Ca2+ active pumps move Ca2+ back into the SR, the Ca2+ level in the sarcoplasm rapidly decreases. Inside the SR are molecules of a protein that binds to Ca2+ called ______________. As a result of this binding, even more Ca2+ can be sequestered (stored) in the SR. In a relaxed muscle fiber the concentration of Ca2+ is 10,000 times higher in the SR than the sarcoplasm.
relaxes
Excitation-contraction coupling: 8. As the Ca2+ level in the sarcoplasm decreases, Ca2+ is released from troponin, tropomyosin covers the myosin-binding sites on actin, and the muscle fiber _____________.
voltage-gated
Excitation-contraction coupling: 1. Located in the T tubule membrane of a triad are integral membrane proteins that function as ______________ Ca2+channels.
action potential
Excitation-contraction coupling: 2. When an ______________ travels along a T tubule, the voltage-gated Ca2+ channels detect the change in voltage and undergo a conformational change.
Ca2+ release channels
Excitation-contraction coupling: 3. This change causes other integral membrane proteins in the terminal cisternal membrane of the sarcoplasmic reticulum called ______________ to open and release Ca2+ from the SR into the sarcoplasm around the thick and thin filaments.
cross-bridges
Excitation-contraction coupling: 4. The concentration of Ca2+ rises tenfold or more and the released Ca2+ combines with troponin, causing it to undergo a conformational change that that causes tropomyosin to move away from the myosin-binding sites on actin. Once the myosin-binding sites are free, myosin heads bind to them to form _____________ and the muscle fiber contracts.
active transport
Excitation-contraction coupling: 5. The terminal cisternal membrane of the sarcoplasmic reticulum also contains Ca2+ _______________ pumps that use ATP to constantly move Ca2+ from the sarcoplasm into the SR.
sarcomeres
Filaments and the Sarcomere: The filaments inside a myofibril do not extend the entire length of a muscle fiber. Instead, they are arranged in compartments called _____________.
striated
Filaments and the Sarcomere: The pattern of overlap of thick and thin filaments consists of zones and bands, which cause the ____________ appearance of skeletal muscle.
filaments (myofilaments)
Filaments and the Sarcomere: Within myofibrils are smaller protein structures called _________________
(1) Thin (2) Thick
Filaments and the Sarcomere: _____1_____ filaments are composed mostly of the protein actin; _____2_____ filaments are composed mostly of the protein myosin. Both are directly involved in the contractile process.
Thin
Filaments and the Sarcomere: ________ filaments are know as I-filaments (I Bands)= Isotropic. Made up of actin.
Thick
Filaments and the Sarcomere: ________ filaments are known as A-filaments (A bands)= Anisotropic. Made up of myosin.
myofibrils
Filaments and the Sarcomere: _____________ are made of thick filaments (dark banding) and thin filaments (light banding), which in turn are made of protein.
heat
Functions of Muscular Tissue: Producing ________- produces (blank) by the contraction of skeletal muscles, a process called thermogenesis. Much of the head released by muscle is used to maintain normal body temperature.
body movements
Functions of Muscular Tissue: Producing ______________- total (blank) such as walking and running, and localized movements such as grasping a pencil, rely on the integrated functioning of skeletal muscles, bones, and joints.
Muscles
Functions of Muscular Tissue: _________ contract to adjust to what position we are in at the time, running vs sitting.
storing
Functions of Muscular Tissue: __________ and moving substances- temporary storage of food in the stomach, moves blood through the arteries and veins, moves urine
stabilize
Functions of Muscular Tissue: ________________ body positions- (blank) joints and help maintain body positions, such as standing or sitting.
tendons
Structure of Skeletal Muscle: Calf of your leg (belly), it is attached to tibia by ___________.
Aponeuroses
Structure of Skeletal Muscle: Like the muscle belly, tendons display a great variety of shapes: Some are long, ropelike structures, while others are arranged in flat sheets called _________________.
muscle belly (body)
Structure of Skeletal Muscle: The reddish or meat like appearance that we associate with muscular tissue arises from the large population of well-vascularized muscle cells in the _____________ of the organ connected by tendons to the skeleton.
tendons
Structure of Skeletal Muscle: ______________- a tough, white fibrous cord of dense regular connective tissue that attaches the muscle belly to the bones. They are avascular, and are composed of parallel arrangements of collagen fibers at the end of bones. It is an extension of the perimysium- surrounds the fascicles, epimysium, endomysium
actin myosin
Structure of thick and thin filaments: You have to have ________ and _______ in order for there to be a contraction.
eccentric
Isotonic and Isometric Contractions: ______________ isotonic contraction- When the length of a muscle increases during a contraction, the contraction is this. During an (blank), the tension exerted by the myosin cross-bridges resists movement of a load (the book, in this case) and slows the lengthening process.
concentric
Isotonic and Isometric Contractions: ______________ isotonic contraction- if the tension generated is great enough to overcome the resistance of the object to be moved, the muscle shortens and pulls on its tendon to produce movement and to reduce the angle at a joint. Picking up a book from a table involves these contractions of the biceps brachii muscle in the arm.
M line
The Arrangement of Filaments within a Sarcomere: The ______________ is the band of proteins that holds the sarcomere together
H zone
The Arrangement of Filaments within a Sarcomere: The ______________ is the middle of the sarcomere
cross-bridges
The Contraction Cycle: Attachment of myosin to actin to form _______________- The energized myosin head attaches to the myosin-binding site on actin and releases the phosphate group. When the myosin heads attach to actin during contraction, they are referred to as (blank)
myosin
The Contraction Cycle: Detachment of _______________ from actin- At the end of the power stroke, the cross-bridge remains firmly attached to actin until it binds another molecule of ATP. As ATP binds to the ATP-binding site on the myosin head, the myosin head detaches from actin.
power stroke
The Contraction Cycle: _______________- After the cross-bridges form, the power stroke occurs. During the power stroke, the site on the cross-bridge where ADP is still bound opens. As a result, the cross-bridge rotates and releases the ADP. The cross-bridge generates force as it rotates toward the center of the sarcomere, sliding the thin filament past the thick filament toward the M line.
ATP hydrolysis
The Contraction Cycle: _______________- The myosin head includes an ATP-binding site and an ATPase, an enzyme that breaks down ATP into ADP (adenosine diphosphate) and a phosphate group. This reaction reorients and energizes the myosin head. Notice that the ADP and a phosphate group are still attached to the myosin head.
False (THEY HAVE TO INTERTWINE OR IT WILL NOT WORK)
True or False: Myosin tails don't have to intertwine
true
True or False: Muscle tissue is strained
red
Types of Skeletal Muscle Fibers: ________ muscle fibers- muscle fibers with a high myoglobin content
white
Types of Skeletal Muscle Fibers: ________ muscle fibers- muscle fibers with low myoglobin content
slow oxidative (SO)
Types of Skeletal Muscle Fibers: ________________ fibers- skeletal muscle fibers that contain a high myoglobin content, many blood capillaries, and appear red in color; they are adapted for maintaining posture and endurance-type activities such as running a marathon; also called type I fibers. They generate ATP mainly by aerobic cellular respiration, which is why they are called oxidative fibers. They use ATP at a slow rate, so the fibers have a slow speed of contraction.
fast oxidative-glycolytic (FOG)
Types of Skeletal Muscle Fibers: ________________ fibers- skeletal muscle fibers that have a high hemoglobin content and many blood capillaries and appear dark red; they contribute to activities such as running and walking; also called type IIa fibers which are typically the largest. They can generate considerable ATP by aerobic cellular respiration, which gives them a moderately high resistance to fatigue. They can also generate ATP by anaerobic glycolysis. They are "fast" fibers because they use ATP at a fast rate.
Fast glycolytic (FG)
Types of Skeletal Muscle Fibers: ________________ fibers- skeletal muscle fibers that have a low myoglobin content, relatively few blood capillaries and mitochondria, and appear white in color; they contract strongly and quickly and are adapted for intense anaerobic movements of short duration, for example, weight lifting; also called type IIb fibers. They use ATP at a fast rate, so they contract strongly and quickly; called fast-twitch fibers, but fatigue quickly
myosin and actin
What are the 2 contractile proteins?
Tropomyosin and Troponin
What are the 2 regulatory proteins?
flexes toes
What is the action of the flexor digitorum brevis?
adduct toes
What is the action of the plantar interossei?
extends leg
What is the action of the rectus femoris?
Ligamentum nuchae
What is the ligament that goes all the way down, gives you stability for your head and cervical column C1/2?
flexes leg
What is the principal action of the muscle indicated by line B?
trumpeter's muscle
Which best describes the buccinator?
swimmer's muscle
Which best describes the latissimus dorsi?
tailor's muscle
Which best describes the sartorius?
fibularis (peroneus) longus and tibialis anterior
Which two muscles provide a good example of an "antagonistic pair"?
biceps femoris and semitendinosus
Which two muscles provide good examples for use of the term "synergists"?
muscle compartment
_________________- is a group of skeletal muscles that arose from a common developmental origin. As they develop, the nerves and blood vessels develop along with them. Because of this, they share common blood and nerve supply. Also because they are grouped on the same side of joints, the anterior compartment muscles are typically flexors of the joints they cross, and posterior compartment muscles are typically extensors of the joints they cross.
smooth muscle
__________________ tissue- Involuntary, non-striated, uninucleate, and tapered cells
fulcrum
Lever Systems: __________- a lever is a rigid structure that can move around a fixed point called this
effort
Lever Systems: __________- force which causes movement; the force exerted by muscular contraction.
load (resistance)
Lever Systems: __________- force which opposes movement; is typically the weight of the body part that is moved or some resistance that the moving body part is trying to overcome (such as the weight of a book you might be picking up).
second-class
Lever Systems: ____________ levers- An example is standing up on your toes. The fulcrum is the ball of the foot. The load is the weight of the body. The effort (E) is the contraction of the muscles of the calf, which raise the heel off the ground.
third-class
Lever Systems: ____________ levers- The effort is between the fulcrum and the load. These levers operate like a pair of forceps and are the most common levers in the body. Third-class levers always produce a mechanical disadvantage because the effort is always closer to the fulcrum than the load. In the body, this arrangement favors speed and range of motion over force. (Elbow joint, the biceps brachii muscle, and the bones of the arm and forearm are examples of this)
third-class
Lever Systems: ____________ levers- The elbow joint, the biceps brachii muscle, and the bones of the arm and forearm are one example of a this lever. As we have seen, in flexing the forearm at the elbow, the elbow joint is the fulcrum , the contraction of the biceps brachii muscle provides the effort (E), and the weight of the hand and forearm is the load .
first-class
Lever Systems: ____________ levers- The fulcrum is between the effort and the load. It can produce either a mechanical advantage or mechanical disadvantage depending on whether the effort or the load is closer to the fulcrum. (Think of an adult and a child on a seesaw.) (One example is the lever formed by the head resting on the vertebral column)
second-class
Lever Systems: ____________ levers- The load is between the fulcrum and the effort. operate like a wheelbarrow. They always produce a mechanical advantage because the load is always closer to the fulcrum than the effort. This arrangement sacrifices speed and range of motion for force; this type of lever produces the most force. (Standing up on your toes)
first-class
Lever Systems: ____________ levers- When the head is raised, the contraction of the posterior neck muscles provides the effort (E), the joint between the atlas and the occipital bone (atlanto-occipital joint) forms the fulcrum , and the weight of the anterior portion of the skull is the load .
Mechanical advantage
Lever systems: _________________- if the load is closer to the fulcrum and the effort farther from the fulcrum, then only a relatively small effort is required to move a large load over a small distance
mechanical disadvantage
Lever systems: _________________- if the load is farther from the fulcrum and the effort is applied closer to the fulcrum, then a relatively large effort is required to move a small load (but at greater speed).
hyperplasia
Microscopic Anatomy of a Skeletal Muscle Fiber (Cell): ___________- an abnormal increase in the number of normal cells in a tissue or organ, increase in cell number.
hypertrophy
Microscopic Anatomy of a Skeletal Muscle Fiber (Cell): ___________- an excessive enlargement or overgrowth of tissue without cell division; increase in cell size. This is the dramatic muscle growth that occurs after birth occurs by enlargement of existing muscle fibers.
muscle fibers (genetically predisposed to be muscular)
Microscopic Anatomy of a Skeletal Muscle Fiber (Cell): ____________- the most important components of a skeletal muscle. Born with a set amount, will have them forever.
sarcoplasmic reticulum (SR)
Microscopic Anatomy: ________________- a network of saccules and tubes surrounding myofibrils of a muscle fiber, comparable to endoplasmic reticulum; functions to reabsorb calcium ions during relaxation and to release them to cause contraction. When triggered, calcium will be released from the terminal cisterns into the sarcoplasm, which triggers muscle contraction. It stores Ca^2+ until needed
myofibrils
Microscopic Anatomy: ________________- a threadlike structure, extending through a muscle fiber consisting mainly of thick filaments (myosin) and thin filaments (actin, troponin, and tropomyosin); they are non-membrane bound organelles, they are smaller than fibers. They extend the entire length of the muscle fiber, have prominent striations that make the whole muscle fiber look striped. Separated by sarcoplasmic reticulum (SR)
triad
Microscopic Anatomy: ________________- made up of the transverse tubules and the terminal cisterns
sarcolemma
Microscopic Anatomy: ________________- the plasma membrane that surrounds a skeletal muscle fiber
sarcoplasm
Microscopic Anatomy: ________________- the sarcolemma surrounds this; the cytoplasm of a skeletal muscle fiber. Includes a substantial amount of glycogen, a storage molecule that consists of a chain of linked glucose molecules.
transverse tubules (T tubules)
Microscopic Anatomy: ________________- thousands of tiny invaginations of the sarcolemma; are extensions of the plasma membrane, they tunnel in from the surface toward the center of the muscle fiber. They are open to the outside of the fiber, they are filled with interstitial fluid. The muscle action potentials propagate along the sarcolemma and through the these, quickly spreading throughout the muscle fiber. Mitochondria are in here because you have to have ATP in muscle contraction.
myofilaments (smallest to largest)
Microscopic Anatomy: _________________ make up myofibrils that make up myofibers
contractile
Muscle Proteins: _______________ proteins- proteins that generate force during muscle contractions
contractile
Muscle Proteins: The two __________ proteins in muscle, myosin and actin, are components of thick and thin filaments, respectively.
structural
Muscle Proteins: __________ proteins- Proteins that keep the thick and thin filaments of the myofibrils in proper alignment, give the myofibrils elasticity and extensibility, and link the myofibrils to the sarcolemma and extracellular matrix.
regulatory
Muscle Proteins: ____________ proteins- proteins that help switch the muscle contraction process on and off
actin
Muscle Proteins: Contractile: Individual __________ molecules join to form an actin filament that is twisted into a helix. On each actin molecule is a myosin-binding site, where a myosin head can attach.
myosin
Muscle Proteins: Contractile: ___________- the contractile protein that makes up the thick filaments of muscle fibers; it functions as a motor protein in all three types of muscle tissue.
actin
Muscle Proteins: Contractile: ___________- the contractile protein that makes up the thin filaments of muscle fibers
contractile
Muscle Proteins: Myofibrils are built from 3 kinds of proteins- ___________ proteins- these generate force during contraction; myosin and actin (are components of thick and thin filaments), they are sliding over each other and shortens the sarcomere
regulatory
Muscle Proteins: Myofibrils are built from 3 kinds of proteins- ___________ proteins- these help switch the contraction process on and off; make the contraction, turn it on and off= troponin and tropomyosin. They keep the thick and thin filaments in proper alignment.
structural
Muscle Proteins: Myofibrils are built from 3 kinds of proteins- ___________ proteins- these keep the thick and thin filaments in the proper alignment, give the myofibril elasticity and extensibility, and link the myofibrils to the sarcolemma and extracellular matrix.
tropomyosin
Muscle Proteins: Regulatory: ____________- A regulatory protein that is a component of the thin filament. When a skeletal muscle fiber is relaxed, it covers the myosin-binding sites on actin molecules, thereby preventing myosin from binding to actin.
troponin
Muscle Proteins: Regulatory: ____________- A regulatory protein that is a component of the thin filament. When calcium ions (Ca2+) bind to this, it undergoes a change in shape; this conformational change moves tropomyosin away from myosin-binding sites on actin molecules, and muscle contraction subsequently begins as myosin binds to actin.
dystrophin
Muscle Proteins: Structural: __________- A structural protein that links the thin filaments of the sarcomere to integral membrane proteins in the sarcolemma, which are attached in turn to proteins in the connective tissue matrix that surrounds muscle fibers. It is thought that dystrophin helps reinforce the sarcolemma and that it helps transmit tension generated by sarcomeres to tendons.
nebulin
Muscle Proteins: Structural: __________- A structural protein that wraps around the entire length of each thin filament; it helps anchor the thin filaments to the Z discs and regulates the length of the thin filaments during development.
myomesin
Muscle Proteins: Structural: __________- a structural protein that forms the M line. The proteins bind to titin and connect adjacent thick filaments to one another. It holds the thick filaments in alignment at the M line.
Titin
Muscle Proteins: Structural: __________- a structural protein that spans half a sarcomere, from a Z disc to an M line. It anchors a thick filament to both a Z disc and the M line, thereby helping stabilize the position of the thick filament. The part of the molecule that extends from the Z disc to the beginning of the thick is very elastic.
isotonic
Muscle Tone: _____________ contraction- the tension (force of contraction) in the muscle remains almost constant while the muscle changes its length. Isotonic contractions are used to produce body movements and for moving objects. The two types of (blank) contractions are concentric and eccentric.
isometric
Muscle Tone: _____________ contraction- the tension generated is not enough to exceed the resistance of the object to be moved and the muscle does not change its length. An example would be holding a book steady using an outstretched arm. These contractions are important for maintaining posture and for supporting objects in a fixed position. Although isometric contractions do not result in body movement, energy is still expended, as you well know if you have ever tried to hold your anatomy book in an outstretched hand for any length of time.
innervation
Muscle attachment sites: _________- You are also given the nerve or nerves that cause contraction of each muscle. In general, cranial nerves, which arise from the lower parts of the brain, serve muscles in the head region. Spinal nerves, which arise from the spinal cord within the vertebral column, (blank) muscles in the rest of the body.
origin
Muscle attachment sites: _________- the attachment of a muscle tendon to a stationary bone or the end opposite the insertion
insertion
Muscle attachment sites: _________- the attachment of the muscle's other tendon to the movable bone (inner layer of muscle of the pharynx composed of three muscles that elevate the larynx and pharynx during deglutition and speech)
action
Muscle attachment sites: _________- the main movements that occur when the muscle contracts
Muscle
Nerve and Blood Supply: ____________ will have nerves arteries and veins, it has the capability of carrying both sensory and motor information.
NMJ (Neuromuscular junction)
Nerve and Blood Supply: _________________- the near point of contact between the somatic motor neuron and the skeletal muscle fiber
neurovascular bundle
Nerve and Blood Supply: _________________- the nerves and blood vessels innervating a muscle; nerves typically enter the muscle along with the main blood vessels of the muscle as a unknit called this. They enter the muscle body near the stable tendon attachment and then spread through the muscle via the connective tissue channels formed by perimysium and endomysium as they wrap the muscle cells.
somatic motor neurons
Nerve and Blood Supply: _________________- the neurons (nerve cells) that stimulate skeletal muscle fibers to contract are called this. It has a threadlike extension, called an axon, which travels from the neuron cell body in the brain or spinal cord to a group of skeletal muscle fibers in a muscle of the body. Individual cells or neurons innervates skeletal muscle fibers
contractility
Properties of Muscular Tissue: _______________- is the ability of muscular tissue to contract (shorten) forcefully when stimulated by an action potential, and causes movement. When this happens, it generates tension while pulling on its attachment points. (Ex: holding a book in your outstretched hand)
elasticity
Properties of Muscular Tissue: _______________- is the ability of muscular tissue to return to its original length and shape after contraction or extension.
electrical excitability
Properties of Muscular Tissue: _______________- the property of both muscle and nerve cells, is the ability to respond to certain stimuli (external or internal) by producing electrical signals called action potentials (impulses). (EX: get hungry, stomach growls)
tendons
Skeletal muscles cause movements by exerting force on _______, which pull on bones or other structures
multiunit
Smooth Muscle Tissue: _______________ smooth muscle tissue- less common type of smooth muscle tissue that consists of individual fibers, each of which has its own motor neuron terminals; found in walls of larger arteries, airways to the lungs, arrector pili muscle of hair follicles, muscles that control pupil diameter, and ciliary body that focuses the lens of the eye.
visceral (single unit)
Smooth Muscle Tissue: _______________ smooth muscle tissue- more common type of smooth muscle tissue found in skin, walls of small arteries and veins, and walls of hollow viscera such as the stomach, intestines, uterus, and urinary bladder. Because the fibers connect to one another by gap junctions, muscle action potentials spread rapidly throughout the network.
gap junctions
Cardiac muscle tissue: _________________- cell junctions that allow muscle action potentials to spread from one cardiac muscle fiber to its neighbors.
Autorhythmicity
Cardiac muscle tissue: _________________- the ability to repeatedly generate spontaneous action potentials. In the heart, these action potentials cause alternating contraction and relaxation of the heart muscle fibers.
intercalated discs
Cardiac muscle tissue: _________________- the ends of cardiac muscle fibers connect to neighboring fibers by an irregular transverse thickening of sarcolemma that contains desmosomes, which hold cardiac muscle fibers (cells) together, and gap junctions, which aid in conduction of muscle action potentials from one fiber to the next.
desmosomes
Cardiac muscle tissue: _________________- the intercalated discs contain these, which hold the fibers together
Striated
Cardiac muscle tissue: ______________ like skeletal muscle, involuntary movement. They are uninucleate which means they usually have one centrally located nucleus, and branched
tenosynovitis (tendonitis)
Clinical Connection: _____________- is an inflammation of the tendons, tendon sheaths, and synovial membranes surrounding certain joints. The tendons most often affected are at the wrists, shoulders, elbows, finger joints, ankles, and feet. The affected sheaths sometimes become visibly swollen (inflamed) because of fluid accumulation. Tenderness and pain are frequently associated with movement of the body part. The condition often follows trauma, strain, excessive exercise, or other stressors.
fibromyalgia
Clinical Connection: ________________- is a chronic, painful, nonarticular rheumatic disorder that affects the fibrous connective tissue components of muscles, tendons, and ligaments. A striking sign is pain that results from gentle pressure at specific "tender points." Even without pressure, there is pain, tenderness, and stiffness of muscles, tendons, and surrounding soft tissues. In addition to muscle pain, people suffering from this report severe fatigue, poor sleep, headaches, depression, irritable bowel syndrome, and inability to carry out their daily activities. There is no specific identifiable cause., and no known cure. Treatment consists of stress reduction, regular exercise, application of heat, gentle massage, physical therapy, medication for pain, and a low-dose antidepressant to help improve sleep.
Muscular dystrophy
Clinical Connection: _____________- refers to a group of inherited muscle-destroying diseases that cause progressive degeneration of skeletal muscle fibers.
Myasthenia gravis
Clinical Connection: ______________- is an autoimmune disease that causes chronic, progressive damage of the neuromuscular junction. The immune system inappropriately produces antibodies that bind to and block some ACh receptors, thereby decreasing the number of functional ACh receptors. As the disease progresses, more ACh receptors are lost. Thus, muscles become increasingly weaker, fatigue more easily, and may eventually cease to function. The muscles of the face and neck are most often affected. Initial symptoms include weakness of the eye muscles, which may produce double vision, and weakness of the throat muscles that may produce difficulty in swallowing. Later, the person has difficulty chewing and talking. Eventually the muscles of the limbs may become involved. Death may result from paralysis of the respiratory muscles, but often the disorder does not progress to this stage.
muscular atrophy
Clinical Connection: _______________- is a wasting away of muscles. Individual muscle fibers decrease in size as a result of progressive loss of myofibrils. Atrophy that occurs because muscles are not used is termed disuse atrophy. Bedridden individuals and people with casts experience disuse atrophy because the flow of nerve impulses (nerve action potentials) to inactive skeletal muscle is greatly reduced, but the condition is reversible.
hypotonia
Clinical Connection: _________________- refers to decreased or lost muscle tone. Such muscles are said to be. Flaccid muscles are loose and appear flattened rather than rounded. Certain disorders of the nervous system and disruptions in the balance of electrolytes (especially sodium, calcium, and, to a lesser extent, magnesium) may result in flaccid paralysis, which is characterized by loss of muscle tone, loss or reduction of tendon reflexes, and atrophy (wasting away) and degeneration of muscles.
hypertonia
Clinical Connection: _________________- refers to increased muscle tone and is expressed in two ways: spasticity or rigidity. Spasticity is characterized by increased muscle tone (stiffness) associated with an increase in tendon reflexes and pathological reflexes. Rigidity refers to increased muscle tone in which reflexes are not affected, as occurs in tetanus.
extensibility
Properties of Muscular Tissue: _______________- is the ability of muscular tissue to be stretched without being damaged. (Ex: each time your stomach fills with food, the muscle in the wall is stretched).
muscle action potential
Steps of a Nerve Impulse: Step 3: Production of ___________________- The inflow of Na+ triggers a (blank). Each nerve impulse normally elicits one (blank). The (blank) then propagates along the sarcolemma into the system of T tubules. This causes the sarcoplasmic reticulum to release its stored Ca2+ into the sarcoplasm and the muscle fiber subsequently contracts.
termination
Steps of a Nerve Impulse: Step 4: __________ of ACh activity- The effect of ACh binding lasts only briefly because ACh is rapidly broken down by an enzyme called acetylcholinesterase (AChE). This enzyme is attached to collagen fibers in the extracellular matrix of the synaptic cleft. AChE breaks down ACh into acetyl and choline, products that cannot activate the ACh receptor.
ACh
Steps of a Nerve Impulse: Step 1: Release of ________- Arrival of the nerve impulse at the synaptic end bulbs stimulates voltage-gated channels to open, and Ca2+ enters the synaptic end bulbs. Voltage-gated channels are integral membrane proteins that open in response to a change in membrane potential (voltage). The Ca2+ stimulates synaptic vesicles to undergo exocytosis. During exocytosis, the synaptic vesicles fuse with the motor neuron's plasma membrane, liberating (blank) into the synaptic cleft. The (blank) then diffuses across the synaptic cleft between the motor neuron and the motor end plate.
receptors
Steps of a Nerve Impulse: Step 2: Activation of ACh ___________- Binding of two molecules of ACh to the (blank) on the motor end plate opens an ion channel in the ACh (blank). Once the channel is open, small cations, most importantly Na+, can flow across the membrane.
axon terminal
The Neuromuscular Junction: __________- at the NMJ, the end of the motor neuron, divides into a cluster of synaptic end bulbs
neurotransmitter
The Neuromuscular Junction: __________- one of a variety of molecules within axon terminals that are released into the synaptic cleft in response to a nerve impulse, and that change the membrane potential of the postsynaptic neuron.
synapse
The Neuromuscular Junction: __________- the functional junction between two neurons or between a neuron and an effector, such as a muscle or gland; may be electrical or chemical; it is a region where communication occurs between two neurons, or between a neuron and a target cell- in this case, between a somatic motor neuron and a muscle fiber.
synaptic cleft
The Neuromuscular Junction: __________- the narrow gap at a chemical synapse that separates the axon terminal of one neuron from another neuron or muscle fiber (cell) and across which a neurotransmitter diffuses to affect the postsynaptic cell
motor end plate
The Neuromuscular Junction: _____________- the region of the sarcolemma of a muscle fiber (cell) that includes acetylcholine (Ach) receptors, which bind Ach released by synaptic end bulbs of somatic motor neurons.
synaptic end bulb
The Neuromuscular Junction: Axon terminal- _____________- expanded distal end of an axon terminal that contains synaptic vesicles
Acetylcholine (ACh)
The Neuromuscular Junction: Axon terminal- _____________- inside each synaptic vesicle, a neurotransmitter liberated by many peripheral nervous system neurons and some central nervous system neurons. It is the neurotransmitter released at the NMJ.
synaptic vesicles
The Neuromuscular Junction: Axon terminal- _____________- suspended in the cytosol within each synaptic end bulb are hundreds of membrane-enclosed sacs that store neurotransmitters
psoas major
The muscle indicated by line A is the...
abducts the scapula
The muscle indicated by line G is?
genetically
The relative ratio of fast glycolytic (FG) and slow oxidative (SO) fibers in each muscle is _________ determined and helps account for individual differences in physical performance.
excitation-contraction coupling
The sequence of events that links excitation (a muscle action potential) to contraction (sliding of the filaments) is referred to as _______________________.
Motion
________ occurs when the effort applied to the bone at the insertion exceeds the load.
Nerves
____________ and blood vessels develop along with muscles in a particular compartment
isotonic
____________ contraction- tension developed in the muscle remains almost constant while the muscle changes its length
concentric
_____________ contraction- a contraction in which a muscle shortens as it produces a constant tension and overcomes the load it is moving
eccentric
_____________ contraction- contraction in which a muscle lengthens a it produces a constant tension and overcomes the load it is moving.
myology
_____________- is the scientific study of the structure, function, and diseases of skeletal, cardiac, and smooth muscular tissues. - Muscular tissue accounts for 40 to 50% (average) of total body mass.
Articulating
______________ bones usually do not move equally in response to contraction
Cardiac muscle
______________ fibers are shorter in length and less circular in transverse section. They also exhibit branching, which gives individual cardiac muscle fibers a "stair-step" appearance. The muscle tissue has an endomysium, but lacks a perimysium and epimysium
Smooth muscle
______________ fibers have thick and thin filaments but no transverse tubules and little sarcoplasmic reticulum.
filaments (myofilaments)
______________- Contractile proteins within myofibrils that are of two types: thick filaments composed of myosin and thin filaments composed of actin, tropomyosin, and troponin; the sliding of the thin filaments past the thick filaments produces muscle shortening.
muscle fiber (cell)
______________- Long cylindrical cell covered by a vascular endomysium. The cell membrane, the sarcolemma, surrounds the sarcoplasm with its myofibrils, many peripherally located nuclei, mitochondria, transverse tubules, sarcoplasmic reticulum, and terminal cisterns. The fiber has a striated appearance.
myofibril
______________- Threadlike contractile elements within the sarcoplasm of a muscle fiber that extend the entire length of the fiber; composed of filaments.
muscle tone
______________- a sustained, partial contraction of portion of a skeletal system or smooth muscle in response to activation of stretch receptors or a baseline level of action potential in the innervating motor neurons
fascicle
______________- is a bundle of muscle fibers wrapped in perimysium.
skeletal muscle
______________- is an organ made up of fascicles that contain muscle fibers (cells), blood vessels, and nerves. The (blank) is wrapped in epimysium.
Skeletal muscle
_______________ fibers vary in their content of myoglobin- the red protein that binds oxygen in muscle fibers (an O2-binding protein)
Muscle bundles
_________________ arise from common masses of embryonic tissue. The limbs, trunk, and head each have a distinct pattern of muscle development
_____________ contraction- The tension generated is not enough to exceed the resistance of the object to be moved and the muscle does not change in length
isometric
