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193 Cards in this Set

  • Front
  • Back
The term myo refers to ________.
Muscle
Sacro refers to ___________ _______.
At the cellular level the, the cytoplasm of a muscle cells is called the _____________.
Muscle Cells
Sarcoplasm
Myology is the study of ___________ and myositis is _______________ of the muscle.
Muscles
Inflammation
In general the nervous system gives the orders and the muscular system ____________.
Carries them out.
What is it called when a muscle cell gets smaller? When it gets larger?
Atrophy
Hypertrophy
What is it called when a muscle cell increase in size due to the increase in the number of cells?
Hyperplasia
What is the term for when a muscle cell has a change in the structure of the cell?
Metaplasia
Skeletal muscle ___________ the bones of the skeleton, which in turn ___________ the animal around.
Move
Skeletal muscle is often referred to as ____________ muscle.
Voluntary Striated
It is called voluntary because it is ____________.
Under the control of the conscious mind.
The number of muscle fibers that are stimulated to contract is what?
Strength of Contraction
What is the thick central portion of the muscle called?
Belly
Most muscle attach to bones at both ends by though, fibrous connective tissue bands called __________.
Tendons
Some muscles are attached by broad sheets of fibrous connective tissue called ___________.
Aponeuroses
The prominent aponeuroses is the ___________ that runs lengthwise between the muscles on the animal's ventral midline.
Linea Alba
One of the muscle's attachment sites is generally more stable then the other, this more stable site is called the _________ of the muscle.
Origin
The site that undergoes most of the movement when a muscle contracts is called the ____________.
Insertion
When stimulated by a nerve impulse a muscle _____________.
Contracts (shortens)
What term is used to describe a muscle or muscle group that directly produces a desired movement?
Prime Mover
What is a muscle or muscle group that directly opposes the action of a prime mover?
Antagonist
What is a muscle that contrasts at the same time as a prime mover and assists it in carrying out its actions?
Synergist
What is a muscle that stabilizes joints to allow other movements to take place?
Fixator
Which muscle occurs in the superficial fascia between the skin and the deep fascia covering the skeletal muscles.
Cutaneous Muscles
Cutaneous Muscles are thin and just serve to _______ the skin. Who has the thickest cutaneous muscle, horse or cat?
Twitch
Horse
The most obvious function of the abdominal muscles it to ___________. What are some of their other functions?
Support the abdominal organs, Help flex the back, Assist in various functions of straining (expulsion of feces, urine, and newborn), and in the process of vomiting and regurgitation.
Name the abdominal muscles from outside in.
External Abdominal Oblique
Internal Abdominal Oblique
Transversus Abdominis
Rectus Abdominis
Which abdominal muscle's fibers runs in a caudo-ventral oblique direction?
External Abdominal
Which abdominal muscle's fibers run in a cranio-ventral direction?
Internal Abdominal
Which muscle consist of two strap like muscles that run from the ribs and sternum back to the brim of the pubis?
Rectus Abdominis
Which is the deepest muscle whos fibers run directly downward in a ventral direction?
Transversus Abdominis
The muscles of the thoracic limb function mainly in ____________.
Locomotion
Name the muscles of the extrinsic thoracic limb.
Latissimus Dorsi, Pectoral muscle, Deltoids, Brachiocephalicus, Omotransversarius, Trapezius, Rhomboideus, and Serratus Ventralis.
The latissimus dorsi muscle a broad triangular muscle extends from the _____ to its insertions on the ___________.
Spinal Column
Humerus
What are the 4 pectoral muscles?
They extend from the _______ to the _________, and act as _______ of the front limb.
Descending Superficial Pectoralis, Transverse Superficial Pectoralis, Deep Pectoral, and Xiphihumeralis.
Sternum to Humerus
Adductors
What are the 2 deltoids?
They extend from the _____ to the ________.
These muscles _____ and _________ the shoulder joint.
Spinodeltoid and Acromiodeltoid
Scapula to humerus
Abduct and Flex
What are the 2 heads of the brachiocephalicus?
Their action is to _____ the limb forward and _____ the shoulder.
Cleidocephalicus and Cleidobrachialis
pull and extend
The cleidocephalicus extends from the ____ to the _____.
The cleidobrachialis extends from the _____ to the _____.
Skull to Clavicle tendon
Clavicle tendon to Humerus
Which muscle is not present in horses?
Omotransversarius
The omotransversarius extends from the __________ to the _______. Its action is to ___________ the limb.
Wing of Atlas
Scapula
Advance
The trapezius extends from the _______ to the _______.
Its action is to _______ and ________ the forelimb.
Atlas to Thorax
Elevate and Abduct
The Rhomboideus has 3 heads, name them.
Their action is the _______ the forelimb.
They are shaped like a ________ facing up.
Rhomboideus capitis, Rhomboideus cervicis, and Rhomboideus thoracis.
Elevate
Fan
Rhomboideus Capitis extends from the _______ to the __________.
Occipital bone to the Scapula
Rhomboideus Cervicis extends form the ________ to the _______.
Cervical Vertebrae to the Scapula
Rhomboideus Thoracis extends from the ______ to the _______.
Thoracic Vertebrae to the Scapula
Serratus Ventralis extend from the _______ to the ________, and its action is to _______ the trunk. It is shaped like a ______ facing down.
Cervical Vertebrae to the Scapula
Fan
What is the most powerful of the chewing muscles?
Masseter
The muscles of the neck help support the head and allow the head and neck to _____, _________, and _________.
Flex, Extend, an move laterally.
2 of the main muscles that extend the head and neck are the __________ and the ___________.
Splenius and Trapezius
Another muscle that extends the head and neck and also pulls the front leg forward is the _________ muscle.
Brachiocephalic
The sternocephalic muscle extends form the ________ to the ________ and acts to ________ the head and neck.
Sternum to the base of skull
Flex
The masseter extends from the ______ to the ________, and its action is to ________.
Zygomatic arch to the mandible
Elevate mandible when chewing
The temporalis muscle extend from the _______ to the ________, and its action is to ___________.
Parietal, temporal, frontal, and Occipital bone to the mandible.
Elevates mandible for chewing and moves it laterally,
Which muscle forms along with the brachiocephalicus, the jugular groove.
Sternocephalicus
The sternocephalicus extends from the ______ to the __________ and its action is to ___________.
Sternum to the occipital bone
Depress and draws the head and neck to the side
Which muscle helps the cat to smile?
Platysma
The platysma muscle extends from the ___________ to the __________, and its action is to __________.
Cervical Vertebrae to the fibers around the lips
Draw the commissures of the lips caudally
The infraspinous muscle extends from the _________ to the __________ and its action is to ________ the shoulder joint and _________ the limb at the shoulder.
Scapula to the humerus
Flexes and Abducts
The deltoids are an aginist with which other lateral muscle of the shoulder?
Infraspinous
The supraspinatus extends from the ___________ to the __________ and its action is to _______ the shoulder joint.
Suprespinous fossa to the humerus
Extend
Which other lateral shoulder muscle is an antagonist with the supraspinatus muscle?
Infraspinous Muscle
The subscapularis muscle extends from the ___________ to the _________ and its action is to __________ the limb at the shoulder and ________ the leg medially.
Scapula to the humerus
Adducts and Rotates
The teres major muscle extends from the ______ to the ______. Its action is to ________ the shoulder.
Scapula to the humerus
Flexes
The biceps brachii extends from the ________ to the ____________. Its action is to _______ the elbow and ________ the shoulder.
Scapula to the ulnar and radial tuberosities
Flex and extend
Brachialis muscle extends from the ________ to the ___________, and its action is to ______ the elbow.
Humerus to the ulnar and radial tuberosities
Flex
Triceps Brachii muscle has 3 heads _________, _________, and _______ in most animals but carnivores have a 4th head called the _________ head.
Long, Medial, and Lateral
Accessory
The long head of the triceps brachii begins at the ______, the others have a common origin of ______ and they all insert on the ______. Its action is to ______ the elbow and _____ the shoulder.
Scapula / Humerus to the ulna
Extend and Flex
The two primary antagonistic set of muscles in the limb is the ________ and the _________.
Quads and the Hamstrings
The large gluteal muscles and the hamstring muscle group are ________ muscles of the hip joint.
Extensor
What are the 3 hamstring muscles located on the back of the thigh region?
Biceps Femoris, Semimembranosus, and Semitendinousus.
What are their origins and insertions?
Origin (All) - Ischiatic Tuberosity
Insertion - Biceps = Patella/Tibia Semimem = Femur Semitend = Tibia
What are their actions?
Action - All extend hip and Flexes the stifle, Biceps and Semitend also extends the tarsal joint
What are the 4 quadriceps muscles?
Rectus Femoris, Vastus Lateralis, Vastus Intermedius, Vastus Medialis
What are their origins, insertions, and actions?
Origin - Rectus = Ilium, The rest = Femur
Insertion (All) - Tibial Tuberosity
Action (All) - Extends the stifle joint and flexes the hip.
The tensor fasciae latae extends from the ________ to the ________ and its action is to_______ the hip joint and _______ the stifle.
Ilium to the Femoral Fascia
Flexes and Extends
What is the tendon that is commonly used by surgeons to make cuts and strips to replace the anterior cruciate ligament during repair?
Fasciae Latae
Superficial Gluteal Muscle extends from the _______ to the ________ and its action is to ________ the limb and ________ the hip.
Sacrum and Coccygeal Vertebrae to the femur
Abduct and Extend
Middle Gluteal Muscle extend from the ______ to the ______. Its action is to ________ the limb and ________ the hip.
Ilium to Femur
Abducts and Extends
Deep Gluteal Muscle extends from the ______ to the __________. Its action is to _______ and _______ the hip.
Ilium and Ischiatic Spine to the Greater Trochanter
Abducts and Extends
What is the longest and widest of the thigh muscles?
Biceps Femoris Muscle
Biceps Femoris extends from the ________ to the _______, and its action is to ______ the hip, ________ the stifle, and ______ the hock.
Pelvis to the patella, tibia, and tuber calcanei
Extends, Flexes, and Extends
Semitendinosus muscle extends from the ________ to the _______ and its action is to _______ the hip, ________ the stifle, and to ________ the tarsal joint.
Ischiatic Tuberosity to the tibia and tuber calcanei
Extend, Flexes, and Extends
Semimembranosus Muscle extends from the ______ to the ______, and its action is to _________ the hip, and _______ the stifle
Ischiatic Tuberosity to the femur and tibia
Extend and Flexes
Sartorius Muscle extends from the ________ to the ________ and its action is to _______ the hip, _______ the stifle, and ________ the stifle.
Ilium to the patella and tibia
Flexes, Extends, and Flexes
Gracilis Muscle extends from the ______ to the _______ and its action is to _____ the limb, _______ the stifle, and ______ the hip and hock.
Pelvic Symphysis to the tibia and tubercalcanei
Adducts, Flexes, and Extends
Which muscle is severed to relieve pain in dogs with chronic hip dysplasia?
Pectineus Muscle
Pectineus muscle extends from the ________ to the _______ and its action is to ______ the limb.
Prepubic Tendon to the femur
Adduct
The adductor muscle consists of 2 muscles, name them.
Which is larger and which is smaller?
Adductor Magnus - Larger
Adductor Longus - Smaller
The adductor muscle extends from the _______ to the ______ and its action is to _______ the limb and to _______ the hip.
Pelvic Symphysis to the Femur
Adduct and Extend
Cranial Tibial Muscle extends from the ______ to the _______ and its action is to _______ the tarsal joint.
Cranial Tibial Border to the metatarsus
Flexes
Long Digital Extensor Muscle extends from the ______ to the _______ and its action is ________ the digital joints, ______ the tarsal joint, and _______ the stifle joint.
Femur to the distal phalanges
Extends, Flexes, and Extends
Peroneus Longus muscle extends from the _______ to the _______ and its action is to _______ the tarsal joint.
Tibia and Fibula to the metatarsals
Flex
Gastrocnemius muscle extends from the _______ to the _______ and its actions is to ______ the tarsus and _____ the stifle.
Femur to the tuber calcanei
Extend and Flexes
Deep Digital Flexor muscles extend from the ________ to the _______ and its action is to _______ the tarsal joints, and ________ the digital joints.
Fibula to the phalanges
Extend and Flexes
Popliteus muscle extends from the _______ to the _______ and its action is to ________ the stifle and _______ the leg medially.
Femur and Tibia
Flexes and Rotates
What is the common name for the Common Calcanean Tendon? Where does it insert? What 5 muscles is it made up of?
Achilles Tendon
Tuber Calcanei
Gastrocnemius, Superficial digital flexor, Semitendinosus, Gracilis, and Biceps Femoris
The muscles that increase the size of the thoracic cavity when they contract are called __________ muscles.
Inspiratory
What are the 2 main inspiratory muscles?
Diaphragm and the external intercostal muscles.
What is the thin, dome-shaped sheet of muscle that separates the thoracic cavity from the abdominal cavity?
Diaphragm
What happens to the diaphragm when the animal breathes in? out?
In = Flattens out
Out = Pushes up / becomes convex
The external intercostal muscle fibers are directed in a ________ direction so they can contract, and _______ the ribs upward and forward.
Oblique
Rotate
Why does expiration not require as much effort as inspiration?
Because of mechanical forces, like gravity, and the elastic nature of the lungs help collapse the rib cage and push air out.
What are the 2 sets of expiratory muscles that aid in the process?
Internal intercostal muscles, and Abdominal Muscles.
The internal intercostal muscles run at ________ to those of the external. When these contract, the ______ the ribs backward, which _______ the size of the thorax.
Right Angles
Rotate
Decreases
Adbominal Muscles simply ________ reducing the space of the peritoneal cavity.
Contract
Name the 4 heads of the abdominal muscles?
External Abdominal Oblique
Transversus Abdominis
Internal Abdominal Oblique
Rectus Abdominis Muscle
Skeletal Muscles are usually called skeletal muscle fibers due to their overall ___________ shape.
Threadlike or fiber-like shape
A system common to skeletal muscles only allow for the transport of impulses and nutrients from the ______ the muscle down to the __________.
Outside
Protein Filaments
Transverse or T tubules extend from the _________ down to the _________.
Sarcolemma to the protein filaments
The miofibrils that make up the muscle fiber are composed of thousands of tiny, contractile protein filaments known as the _______ and _______ filaments.
Actin and Myosin
The dark line in the center of the I band is called the ___________.
Z Band
The area from one Z line to the next Z line is called a ____________.
Sarcomere
What is the basic contraction unit of skeletal muscle?
Sarcomere
Each of the __________ is made up of many sarcomere lined up end to end.
Myofibrils
What is suprascapular nerve - to muscles innervation, supraspinous and infraspinus muscles.
Sweeny
The sites where the ends of motor nerve fibers "connect" to muscle fibers are called __________ ____________.
Neuromuscular Junctions
If a skeletal muscles nerve supply is interrupted for a lengthy period as a result of injury, the muscle will shrink down through a process called ___________.
Atrophy
Within the end of the nerve fiber in a neuromuscular junction are tiny sacs called _________ _________ that contain the chemical neurotransmitter ____________.
Synaptic Vesicles
Acetylcholine
The effect of the acetylcholine on its receptor is very _______ lasting.
Short
An enzyme in the synapse space called _____________, quickly removes the acetylcholine molecule from its receptor and splits it apart.
Acetylcholinesterase
The number of muscle fibers per nerve fiber determines what?
How small a movement will result from a nerve stimulus
What is the term to describe one nerve fiber and all the muscles fibers it innervates?
Motor Unit
Each individual skeletal muscle fiber is surrounded by a delicate connective tissue layer composed of fine, reticular fibers called the ___________.
Endomysium
Groups of skeletal muscle fibers, called ________, are bound together by a tougher connective tissue layer, called the ___________, which is composed of reticular fibers and thick collagen fibers.
Fascicles
Perimysium
Groups of muscle fascicles are surrounded by ___________, a fibrous connective tissue layer composed largely of tough collagen fibers.
Epimysium
The fat deposits are often visible grossly in meat and are called the ________ of the meat
Marbling
When the impulse reaches the sarcoplasmic reticulum, it causes the release of stored ________ into the sarcoplasm.
Calcium ions
As the Ca++ diffuses into the myofibrils, it turns on the contraction process, which is powered by high-energy molecules of __________ ___________.
Adenosine Triphosphate
What is the difference between tetany and tetanus?
Tetany is the contraction and tetanus is the disease.
Muscles will continue to contract after the initial supply of ATP has been used, leaving _______.
ADP
The ADP is phosphorylated again from another source, ________ ____________.
Creatinine phosphate
The presence of ATP is required for __________ or __________ of the myosin from the actin, and also for the _________ of calcium ions to the sarcoplasmic reticulum.
Relaxation or Detachment
Return
Muscle contraction is _____ to _____% efficient in regard to the accomplishment of work. The non-work portion is dissipated as ______.
50-70%
Heat
When the fiber is stimulated to contract, small levers on the myosin filaments, called ________, ratchet back and forth and pull the __________ on both sides toward the center of the myosin filaments.
Bridges
Actin filaments
The combined shortening of all the end-to-end sarcomere in a muscle fiber results in what we call a _______ ___________.
Muscle Contraction
An individual muscle fiber either contracts completely when it receives a nerve impulse or it does not contract at all. What is this know as?
All or none principle
How does the body produce movements that vary in range and strength when individual muscle fibers are doing all or nothing?
By carefully controlling the number of muscle fibers it stimulates for a particular movement.
A single muscle fiber contraction can be divided into 3 phases, ___________, _____________, and __________. How long does each last?
Latent (0.01 seconds), Contraction (0.04 seconds), and Relaxation (0.05 seconds)
Maximum contraction efficiency occurs if the nerve impulses arrive about ________ apart.
0.1 Seconds
Muscle shortening can occur in the absence of action potentials, referred to as _______ or ___________ ___________.
Rigor or Physiologic Contracture
The actin and myosin filaments remain in a continuous contracted state because sufficient ________ is not able to bring about _________.
ATP
Relaxation
What is contracture that occurs after death called?
Rigor Mortis
Contraction strength varies and is achieved by ________ or by ___________.
Multiple motor unit summation or Wave Summation
One motor unit = weak contraction, Large number of motor units = strong contraction, what is this? All gradations of contraction strength are possible, depending on the # of ____ _____ stimulated.
Motor Unit Summation
Motor Units
When a muscle is stimulated to contract before the muscle has relaxed, the strength of the subsequent contraction is increased, what is this called?
Wave Summation
When the frequency is sufficient such that the individual muscle twitches become fused into a single contraction, the strength is at a max, this condition is know as _______.
Tetany
Tetanus is a ____________ disease caused by a potent neurotoxin eloborated by the organism __________ _______. The neurotoxins reaches the ______ and prevents release of an inhibitory transmitter.
Bacterial
Clostridium tetani
CNS
Applying a stimuli of equal intensity a few seconds apart to muscle. Each successive muscle twitch has slightly more strength than the previous one, until optimal contraction strength is reached, is called what?
Treppe or Staircase Phenomenon
What is the difference between Wave Summation and Treppe?
Wave Summation increases the number of muscles contracted, and stimulating it before it had time to relax.
Treppe allows the muscle fiber to relax but is then stimulated quickly.
What are the 6 ways of naming a muscle, give examples.
Action - Flexor Muscles
Shape - Deltoid Muscles
Location - Biceps Brachii Muscle
Direction of fibers - Rectus Abdominis Muscle
# of heads/division -Quadriceps femoris Muscle Attachment sites - Sternocephalic Muscle.
x
The immediate energy source that powers the sliding of the actin and myosin filaments is the compound _______, which is produced by the many ___________ in the muscle fibers.
ATP
Mitochondria
When one of the phosphate groups is slit off ( forming ______), a considerable amount of _______ is released that powers the sliding of the _______ and ________ filaments.
ADP
Energy
Actin and Myosin
The "battery charger" that converts _____ back to _____is another compound in the muscle fiber and is called _______ _______. This is catalyzed by the enzyme ______ _______. What's the "formula" for this?
ADP to ATP
Creatine phosphate (CP)
Creatinine Kinase (CK)
CP + ADP >> (CK) >> C + ATP
The ultimate source of energy use to produce ______ and ____ and keep the whole system operating comes from the _________ of nutrient molecules.
ATP and CP
Catabolism
Two main compounds involved are _______ and ________. _________ is the sugar molecule that is the ________ energy source for most body cells, including the muscle cells.
Glucose and Oxygen
Glucose
Primary
Glucose + Oxygen ---> _______.
Creatine Phosphate (CP)
Glucose is stored in the fibers in the form of ___________, and oxygen is stored attached to large protein molecules called __________.
Glycogen
Myoglobin
As long as the oxygen supply is adequate to keep up with the energy needs of the fiber, the process is known as ________ ________, and the ________ amount of energy is extracted from each glucose molecule.
Aerobic Metabolism
Maximum
Sometimes, during periods of strenuous activity, the need for oxygen _______ the available supply and muscle fibers must shift to what is called ________ ________ to produce the energy required for continued activity.
Exceeds
Anaerobic Metabolism
_________ metabolism is not as efficient as ________ metabolism and results in ______ ______ formation as a byproduct of incomplete glucose breakdown.
Anaerobic
Aerobic
Lactic acid
The _____ _____ can accumulate in the muscle tissue and cause discomfort.
Lactic Acid
Afterward the lactic acid diffuses into the bloodstream and goes to the______, where it is converted back to _______ by a process that requires oxygen.
Liver
Glucose
Glucose is stored as ___________.
Oxygen attaches to large protein molecules called _________.
Glycogen
Myoglobin
________ __________ means that as long as the oxygen supply is adequate to keep up with the energy needs of the muscle fiber.
Aerobic Metabolism
Muscles are less than 100% efficient at converting ________ to useful work. A considerable amount of the energy produced in muscles is lost in the form of ______.
Energy
Heat
_________ activity is one of the major heat-generating mechanisms that the body uses to maintain a constant internal temperature.
Muscular
If heat production exceeds body needs, excess must be eliminated by mechanisms such as _________ or _________.
Panting or Sweating
Under cold conditions, the body may need to increase the production of heat to avoid _________. It often does this by producing the small, spasmodic muscle contractions we know as _________.
Hypothermia
Shivering
Cardiac muscle cells form __________ networks around the cardiac chambers. The ________ and ________ ___________ of cardiac muscle allow it to start contracting early in the _________ period before birth.
Elaborate
Arrangement and Physical Characteristics
Embryonic
Cardiac muscle cells are much __________ than skeletal muscle cells and have only one _______ per cell.
Smaller
Nucleus
The firm end-to-end attachments between cardiac muscle cells, under the microscope appear as ______, _________ lines between the cells.
Dark
Transverse
These attachment sites are called ________ ______, which securely fasten the cells together.
Intercalated Disks
With cardiac muscle, each muscle cell contracts rhythmically with no ________ _________ at all. Each cell contracts at a constant rate set by its own internal clock.
External Stimulation
However, if two cells touch, the _______ contracting cells adopts the ______ cell‘s contraction rate.
Slower
Faster
The ________ _________ system consists entirely of cardiac muscle cells. The impulse that starts each heart beat begins in the heart‘s "pacemaker", or the ________ ________ located in the wall of the right atrium.
Impulse Conduction
Sinoatrial (SA) Node
The nerves to the heart are from both divisions of the autonomic portion of the nervous system, that is, the ___________ and ______________ system.
Sympathetic and Parasympathetic
The ________ fibers stimulate the heart to beat _______ and ______ as part of the _______ or ______ response that kicks in when an animal feels threatened.
Sympathetic
Harder and Faster
Fight or Flight
The __________ fibers do the opposite in that they inhibit cardiac function, there by causing the heart to beat more ______ and with less force when the body is relaxed and resting.
Parasympathetic
Slowly
Sympathetic =
Parasympathetic =
Fight or Flight
Digestion
Smooth Muscle is found in two main forms:
1.
2.
1. Large sheets of cells in the walls of some hollow organs (visceral smooth muscle) and,
2. Small, discrete groups of cells (multiunit smooth muscle).
Smooth muscle cells are small and ______ shaped with a single _______ in the center.
Spindle
Nucleus
They have a ________, ________ appearance under the microscope because their filaments of actin and myosin are not arranged in _______ _________ as in skeletal and cardiac muscle.
Smooth and Homogeneous
Parallel Myofibrils
Small contractile units of actin and myosin filaments ________ the cell at various angles and are attached at both ends to "______ ______" that correspond to the ___ lines of skeletal muscle.
Crisscross
Dense Bodies
Z
Because their contractile units are not organized into regular, parallel sarcomeres, individual smooth muscle cells can ________ to a greater extent than skeletal or cardiac muscle cells.
Shorten
Visceral smooth muscle is found in the walls of many soft, _____ ______, which are also known by the general name _____. Its cells are linked to form large sheets in the walls of organs such as ____, _____, _____ and ____.
Internal Organs
Viscera
Stomach, Intestines, Uterus, and Urinary Bladder
Like cardiac muscle, visceral smooth muscle contracts without the need for _______ ________. It does react to _______, however, by contracting more strongly.
External Stimulation
Stretching
This is useful in the _______ _______, where the presence of food in the lumen stretches the tube and the smooth muscle in its wall.
Gastrointestinal Tract
Like cardiac muscle, the nerve supply to smooth muscle consists of the ______ and _______ divisions of the autonomic nervous system.
Sympathetic and Parasympathetic
Sympathetic stimulation _______ visceral smooth muscle activity, and the parasympathetic stimulation _________ it.
Decreases
Increases
Multiunit smooth muscle is _______ and _______. Multiunit smooth muscle is made up of individual smooth muscle cells or small groups of cells.
Small and Delicate
Contractions of multiunit smooth muscle are not _________. They require impulses from ___________ nerves to contract.
Automatic
Autonomic
The actions of multiunit smooth muscle are ________ and _________ _________. This allow fine control of actions, such as adjusting the size of ___________.
Specific and Carefully Controlled
The pupil of the eye
It also allows delicate control of ____________ throughout the body and airflow through the lungs by adjusting the size of _____ ________ and ___ _________ according to the body‘s needs.
Blood flow
Blood vessels
Air passageways