Muscular System Flashcards by Miyaki Jan Lim

are contractile and supply force for motility (heat production)

Stimulated by nerve impulses

Final determinants of posture, aid in movement of viscera

Muscles

How well did you know this?

Not at all

Perfectly

why are muscles Difficult to establish homologies due to

Variability in muscle shape
Splitting or merging of muscles
O, I & A may change

How well did you know this?

Not at all

Perfectly

Main Functions of muscles

Supply force for movement

Acted as movers and levers for every action with the aid of the skeleton

Restrain motion and hold the body in position

Contraction of the viscera

Heat production (temperature regulation)

How well did you know this?

Not at all

Perfectly

Classification of Muscles

color
location
controlled by the nervous system
embryonic origin
microscopic appearance

How well did you know this?

Not at all

Perfectly

Muscles are classified according to their color

red and white muscles

How well did you know this?

Not at all

Perfectly

This classification has fallen out of favor because such a color distinction alone underestimates the complexity of muscles

Muscles are classified according to their color

How well did you know this?

Not at all

Perfectly

type of muscles that are classified according to their location

muscles that move bones or cartilages

Somatic muscles

How well did you know this?

Not at all

Perfectly

type of muscles that are classified according to their location

control the activity of organs, vessels and ducts

Visceral muscles

How well did you know this?

Not at all

Perfectly

type of muscles that are classified by the way in which they are controlled by the nervous system

Voluntary muscles are under immediate conscious control

involuntary muscles are not under immediate conscious control

How well did you know this?

Not at all

Perfectly

muscles arise from what three embryonic origins

mesenchyme
Paired hypomere
paraxial mesoderm

How well did you know this?

Not at all

Perfectly

muscles arise from three embryonic origins

embryonic origins from which smooth muscles within the wall of the blood vessels and some viscera develop

mesenchyme

How well did you know this?

Not at all

Perfectly

muscles arise from three embryonic origins

embryonic origins that are differentiated into smooth muscle layers of the alimentary tract and its derivatives

Paired hypomere

How well did you know this?

Not at all

Perfectly

muscles arise from three embryonic origins

embryonic origins that are from which most of the skeletal muscles develop

paraxial mesoderm

How well did you know this?

Not at all

Perfectly

Types of Muscles that are classified by their general microscopic appearance

skeletal, cardiac, and smooth muscle

How well did you know this?

Not at all

Perfectly

Structure of Skeletal Muscle

Belly
Fascia
Origin and insertion

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscle as to Action

Agonist or prime mover
Antagonist
Synergist
Fixator

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscle as to Action
principal mover for specific action

Agonist or prime mover

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscle as to Action
for opposite movement

Antagonist

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscle as to Action
helps the stabilize the movement of one joint and inhibit undesirable movements

Synergist

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscle as to Action
fixes the position of the limb when the movement is occurring

Fixator

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscles as to Specific Function

Flexors
Extensors
Adductors
Abductors
Pronators
Supinators
Elevators or levators
Depressors
Constrictors
Dilators
Sphincters

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscles as to Specific Function

bend a limb or one part of a limb against another

Flexors

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscles as to Specific Function

straighten a limb or one of its component parts

Extensors

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscles as to Specific Function

draw a part toward a median line or toward a neighboring part or limb

Adductors

How well did you know this?

Not at all

Perfectly

Types of Skeletal Muscles as to Specific Function draw a part away from a median line or from a neighboring part or limb

Abductors

Types of Skeletal Muscles as to Specific Function turn or rotate a part downward on its axis as in the palm of the hand

Pronators

Types of Skeletal Muscles as to Specific Function turn or rotate a part forward and upward on its axis as in the palm of the hand

Supinators

Types of Skeletal Muscles as to Specific Function raise or lift a part as when the lower jaw in closing the mouth

Elevators or levators

Types of Skeletal Muscles as to Specific Function lower or depress a part as when the lower jaw in opening the mouth

Depressors

Types of Skeletal Muscles as to Specific Function draws part together or compress a space such as the pharynx and the abdomen

Constrictors

Types of Skeletal Muscles as to Specific Function widens an opening or a space

Dilators

Types of Skeletal Muscles as to Specific Function contrictors surrounding an opening such as mouth, pylorus and anus

Sphincters

Basis in Naming Skeletal Muscles

Direction of fibers Location or position Number of divisions Shape Origin and insertion Action Size Some combination

During muscle evolution, some muscles have fused with one another, others have split into distinct new muscles, some have become reduced in prominence, and other have changed their points of attachment and hence their evolution

true

In order to trace the evolution of individual muscle, several criteria for recognizing ___________ muscles must be used

homologous

Criteria for Establishing Muscle Homology

Attachment similarity Functional similarity Similarity in embryonic origin Innervation similarity

Alterations in Muscles

Splitting Fusion Reduction in size Change in point of attachment

Skeletal muscles of the trunk and tail Extend forward beneath the pharynx as hypobranchial muscles and in amniotes as tongue muscles Do not include branchiomeric or appendicular muscles

Axial Muscles

most evident in fish and aquatic amphibians where the axial muscles are used in locomotion relating to or consisting of several similar segments or somites characteristics of Axial Muscles

Metameric

because of their embryonic origin (arise from segmental mesodermal somites) Axial Muscles are also described as

Segmental

Axial Muscles (9)

1 - epaxials (red) 2 - hypaxials 3 - external oblique 4 - internal oblique 5 - transversus abdominis 6 - rectus abdominis 7 - trapezius 8 - dorsalis scapulae 9 - latissimus dorsi

Trunk and Tail Muscles of Fishes Musculature of the body wall and tail of fishes consists of __________ separated by myosepta to which the longitudinally directed muscle fibers attach

myomeres

Trunk and Tail Muscles of Fishes are divided into _______ and ________ portions by a horizontal skeletogenous septum First and foremost role of this musculature is for locomotion

epaxial hypaxial

Agnathans Muscular system of lampreys is more primitive than other vertebrates __________ is lacking, thus the prominent axial musculature is not divided into epaxial and hypaxial divisions

lateral septum

Each myotome contributes one muscle segment called ________

myomere

Agnathans The short fibers of the myomeres are inserted on partitions of connective tissues called ___________, which lie between successive myomeres

myosepta

Agnathans The ventral portions of myomeres behind the pharynx turn forward _____ the hypobranchial musculature

above

Agnathans Branchial muscles are not prominent Muscles encircling the specialized mouth and tongue are _____ but not _______ with muscles of higher vertebrates

prominent homologous

Gnathostomous Fishes Musculature of jawed fishes is more advanced but less complex than _____

tetrapods

Gnathostomous Fishes Strong axial muscles ________ and tail from side to side during swimming

flex the spine

Gnathostomous Fishes Myomeres become __________ to extend the action of each myomere over several vertebrae and to assure that muscle fibers can all shorten at equal rates

more angled (zig-zag shaped) and are molded into interlocking cones

Gnathostomous Fishes Epaxial muscles continue to the skull as __________

epibranchial muscles

Gnathostomous Fishes Strap-like ___________ extend from the pectoral girdle to the visceral arches Serve to open the jaws and pull the gills downward and backward Evolved from the hypaxial muscles retaining the longitudinal orientation of fibers

hypobranchial muscles

Trunk and Tail Muscles of Tetrapods As the limbs take over the propulsive role, the limb muscles _______ and the axial musculature _______ and become more related to the skeleton for dorsoflexion and ventroflexion of the spine

enlarge decreases

Trunk and Tail Muscles of Tetrapods what happens to the Myosepta

regress and disappear

Trunk and Tail Muscles of Tetrapods Muscles _________ that span from two to many vertebrae

develop long fibers

Trunk and Tail Muscles of Tetrapods Certain muscles form_______ and other becomes ______

sheet-like layers associated with the pectoral girdle

__________ muscles of amphibians other than anurans are conservative Myosepta are still present but in vertical orientation instead of angled

Epaxial muscles

Epaxials of _________ lack myosepta and become complex Muscles in the cervical region form layers associated with a flexible neck

reptiles and mammals

Epaxial muscles of ________ are only prominent in the neck

turtles and birds

Collectively functions in extending the vertebral column and in lateral flexion of the body

Epaxial Muscles of the Trunk

Epaxial Muscles of the Trunk Divided arbitrarily into four groups:

Intervertebrals Longissimus Spinales Iliocostales

Epaxial Muscles of the Trunk Deepest of the epaxial muscles and the only one to retain primitive metamerism

Intervertebrals

Intervertebrals are Classified based on location:

Intertransversarii Interapinales Interarcuales Interarticulares

Intervertebrals are Classified based on location: extend between two successive transverse processes

Intertransversarii

Intervertebrals are Classified based on location: extend between two neural spines

Interapinales

Intervertebrals are Classified based on location: extend between two neural arches

Interarcuales

Intervertebrals are Classified based on location: extend between two successive zygapophyses

Interarticulares

is collective term for lumbar intervertebrals grouped with spinales

Multifidous spinae

Axial Muscles Occupy lateral position above the transverse processes and individual bundles are named according to their location: capitis, cervicis and dorsi

Longissimus

Axial Muscles Named as such because it is the longest epaxial mass Dominant extensor in mammals and plays no role in mammalian locomotion The medial bundle continues into the tail as the extensor caudae lateralis

Longissimus

Axial Muscles Occupy medial position above the transverse processes and individual bundles are named according to their location: capitis, cervicis and dorsi

Spinales

Axial Muscles Connect neural spines or transverse process with neural spines several or many segments cephalad Chief role is to assist in maintaining stability of the column

Spinales

Axial Muscles _______ connect transverse processes with the neural spines of the second vertebrae forward

Transversospinales

Axial Muscles Lateral to the longissimus and constitute a thin sheet arising on the ilium and passing forward to insert on the ribs or uncinate processes Continue forward to the neck but not in the tail

Iliocostalis

Dominant epaxials in reptiles which allows for ________ Rotates the pectoral girdle and to a lesser degree the pelvic girdle on a vertical axis in crocodiles

lateral undulation

Similar in all tetrapods and is classified into three groups:

Subvertebral group Rectus abdominis group Oblique and transverse group

Hypaxial Muscles of the Trunk Similar in all tetrapods and is classified into three groups: located below the transverse processes of the vertebrae

Subvertebral group

Hypaxial Muscles of the Trunk Similar in all tetrapods and is classified into three groups: runs lengthwise along the ventral body wall between the two girdles

Rectus abdominis group

Hypaxial Muscles of the Trunk Similar in all tetrapods and is classified into three groups: found on the lateral side of the body

Oblique and transverse group

Form a longitudinal band of fairly powerful flexors of the vertebral column lying beneath the transverse process from the atlas to the pelvis

Subvertebral Muscles

Subvertebral Muscles in neck of birds and mammals

Longus colli

Subvertebral Muscles in the lumbar region with an additional psoas minor in mammals

Quadratus lumborum

Subvertebral Muscles in the spine

Ventroflexes

Extends longitudinally on either side of the linea alba between the pubic symphysis and the sternum

Rectus Abdominis Muscle

Rectus Abdominis Muscle is strictly segmental in _____________ and it exhibits irregular transverse tendinous inscriptions in ________

urodeles anurans and amniotes

muscle is a slip of muscle in the marsupial pouch and eutherians can either have it as vestigial as species characteristic or as an anomaly

Pyramidalis

Muscles that have become stratified into superficial and deep layers Muscle that fibers pass obliquely from origin to insertion

Oblique and Transverse Muscles

Oblique and Transverse Muscles May either be split in two or lost

Aquatic urodeles - external oblique is split into two Crocodilians and some lizards - all layers consist of two sheets each Anurans - internal oblique is sometimes missing Birds - sheet are thin Turtles - all layers are vestigial

is derived from the internal oblique and sometimes the transverse abdominal muscle Well developed in mammals in which the inguinal canal is open because they retract the testis into the abdominal cavity Plays a major role in external respiration in most amniotes other than turtles and has an accessory role in mammals

Cremaster muscle

Oblique and transverse muscles, together with the rectus, ____________ for functions such as egg laying, delivery of mammalian young and emptying of digestive tract

supports the abdominal viscera

Somites from the level of the developing 3rd to 5th cervical spinal nerves migrate caudad in the somatopleure to invade the embryonic septum transversum Consists of a central tendon with a pair of semilunar extensions and a muscular portion Become the major respiratory muscle in mammals

Diaphragm

Continuation of the epaxial and hypaxial musculature of the trunk Most evident in urodeles and generalized reptiles

Muscles of the Tail

Muscles of the Tail Disruption of the continuity occurs to one degree or another at the level of the pelvis of amniotes generally and especially of

birds and mammals

Muscles of the Tail Intervertebrals and multifidous spinae continue as ______ and longissimus continue as _______

medial lateral extensors

Muscles of the Tail Long hypaxial muscle arise from the medial surface and caudal border of the wing of the ilium, from transverse processes of the last lumbar vertebrae or from the sacrum pass into the tail and bend the tail ______________

lateral or downward

Develop from the upper part of the postotic somites and several of the trunk somites Lie above the gill region Elevate the cranium when mouth is open (some fishes and amphibians) Extension of epaxial muscles of the trunk

Epibranchial Muscles

From trunk somites that migrated to the floor of the pharynx Lie below the gill region Open jaw and expand pharynx during feeding Cranial extensions of the hypaxial musculature of the tongue

Hypobranchial Muscles

Hypobranchial Muscles Sharks

Prehyoid - coracomandibularis (extend mandible toward pectoral girdle) Posthyoid - rectus cervicis, coracohyoideus and coracoarcuals; extend to pectoral girdle

Hypobranchial and Tongue Muscles Extend forward from the coracoid region of the pectoral girdle via coracoarcuales in fishes inserts on the Meckel’s cartilage

Coracomandiburalis

Hypobranchial and Tongue Muscles Extend forward from the coracoid region of the pectoral girdle via coracoarcuales in fishes insert on the basihyals

Coracohyoideus

Hypobranchial and Tongue Muscles Extend forward from the coracoid region of the pectoral girdle via coracoarcuales in fishes insert on the ventral most segments of the gill cartilages

Coracobranchialis

Stabilize the hyoid apparatus and larynx in tetrapods and draw these cephalad or caudad: sternohyoid, sternothyroid, thyrohyoid, omohyoid and geniohyoid

Hypobranchial and Tongue Muscles

Tongue of amniotes is a ________ anchored to the hyoid skeleton and stuffed with hypobranchial muscles

mucosal sac

The extrinsic tongue muscles are

hyoglossus, styloglossus and genioglossus

The _________ is an intrinsic tounge muscle which develops in mammals and some reptiles

lingualis

Those that insert on the girdles, fins or limbs Most fishes use axial muscle for locomotion as such, the _________ are uncomplicated, exhibit little variety, have little mass and perform a restricted function

Appendicular Muscles

Appendicular muscles are _________ in agnathans

absent

Appendicular muscles in jawed fishes have evolved with fins and is divided into a dorsal and ventral group:

Dorsal mass of extensors (or abductors or levators) moving the fins upward or forward Ventral mass of flexor (or adductors or depressors) moving the fins downward or backward

Far more complex than those of fishes because of the joints in tetrapod limbs

Tetrapods

Tetrapods are Divided into two groups depending on their anatomic origins:

Extrinsic appendicular muscles Intrinsic appendicular muscles

Tetrapods are Divided into two groups depending on their anatomic origins: arising on the axial skeleton or fascia of the trunk and inserting on a girdle or limb

Extrinsic appendicular muscles

Tetrapods are Divided into two groups depending on their anatomic origins: arising on a girdle or limb and inserting more distally on the limb

Intrinsic appendicular muscles

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Dorsal group the most constant muscle

Latissimus dorsi

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Dorsal group

Latissimus dorsi Levator scapulae Levator scapulae ventralis or omotransversarius Levator scapulae dorsalis Rhomboideus - found only in crocodilians among living reptiles Serratus ventralis Trapezius

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Dorsal group survivor of the cucullaris muscle of fishes Originates from neural crest and is a muscle of the pharyngeal arch Cleidotrapezius, acromiotrapezius and spinotrapezius

Trapezius

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Ventral group the group of skeletal muscles that connect the upper extremities to the anterior and lateral thoracic walls Subsumed the general term

pectoral muscles (pectoralis and supracoracoideus)

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Ventral group chief adductor

Pectoralis

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Ventral group Pectoral muscles are seen in their primitive state in what order of amphibia

urodeles

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Ventral group Pectoralis ___________ while the ________ elevate the wings in birds

depress supracoracoideus

Extrinsic Muscles of the Pectoral Girdle and Forelimbs Ventral group _______in mammals became an intrinsic muscle

Supracoracoideus

Intrinsic Muscles of the Pectoral Girdle and Forelimbs Dorsal group

Deltoideus - Inserts on the scapula Spinodeltoideus Acromiodeltoideus Teres major Teres minor Subscapularis Triceps brachii long head Supinator Extensors of manus

Intrinsic Muscles of the Pectoral Girdle and Forelimbs Ventral group

Supraspinatus and infraspinatus (homologous with the supracoracoideus) Coracobrachialis Biceps brachii Brachialis Anconeus Epitrochleoanconeus Pronators Flexors of manus

Intrinsic Muscles of the Pectoral Girdle and Forelimbs which extends from the clavicle to the humerus or ulna is present in some mammals Appears to be the continuation of the clavotrapezius in cats

Cleidobrachialis

Musculature of birds is essentially reptilian how so?

Intrinsic muscles of the wings have been reduced Weight is borne by the extrinsic muscles of the forelimb and intrinsic muscles of the hindlimbs

Muscles of the Pelvic Girdle and Hind Limbs Dorsal group

Psoas Iliacus Pectineus Quadratus femoris Rectus femoris - adducts the thigh Vastus group - extend the leg Sartorius - longest muscle in humans Tensor fascia latae Abducts the thigh Gluteus Pyriformis Gemelli Tibialis anterior Peroneus Extensors of the digits

Muscles of the Pelvic Girdle and Hind Limbs Ventral Group

Obturator - abducts the thigh Adductor femoris Caudofemoralis - not locomotor in urodeles but extends its pull in the trunk Flexors of the leg Semitendinosus Biceps femoris Semimembranosus Gracilis Gastrocnemius - extensor Soleus Plantaris Flexors of the digits

Somitomeric and Somitic Muscles of the Head Sharks closing force, largest and strongest

Adductor mandibulae

Somitomeric and Somitic Muscles of the Head Sharks protracts jaws

Preorbitalis

Somitomeric and Somitic Muscles of the Head Sharks open/close spiracle

Spiracularis

Somitomeric and Somitic Muscles of the Head Sharks prey capture

Levator palatoquadrati

Somitomeric and Somitic Muscles of the Head Sharks compress throat

Intermandibularis

Somitomeric and Somitic Muscles of the Head Tetrapods in mammals they are composed of temporalis, masseter, pterygoideus

Adductor mandibulae

Somitomeric and Somitic Muscles of the Head Tetrapods levator and protractor pterygoidei except mammals

Levator palatoquadrati

Somitomeric and Somitic Muscles of the Head Tetrapods mammalian mylohyoid and cranial digastricus (pump air into lungs of amphibians)

Intermandibularis

Muscles of the Hyoid Arch Sharks Suspend jaw and compress pharynx

Levator hyomandibulae Dorsal hyoid constrictor Ventral hyoid constrictor Interhyoideus

Muscles of the Hyoid Arch Amphibians & Reptiles

Ventral hyoid constrictor - sphincter coli Depressor mandibuli - new muscle in tetrapods

Muscles of the Hyoid Arch Mammals Ventral hyoid constrictor

stapedius

Muscles of the Hyoid Arch Mammals new muscle for opening jaw

Digastricus

Muscles of the Hyoid Arch Mammals new muscle for opening jaw

platysma and facial muscles (for facial expression)

Muscles of the Successive Pharyngeal Arches Sharks - raise pharyngeal wall Branchial adductors and superficial - expand and compress pharynx and gills - connect branchial arch segments

Cucullaris constrictors Interbranchialis

Muscles of the Successive Pharyngeal Arches Amphibians & Reptiles - raise pharynx - vocalization

Cucullaris and levatores arcuum Dilator laryngis

Branchiomeric Muscles

Stapedius temporalis Cleido-occipitalis Stylohoideus Sternomastoideus Masseter Cricothyroideus

Extrinsic Integumentary Muscles

'Anterioir Auricular Superior Auricular Caninus Platysma

Intrinsic Integumentary Muscle

Arrector pili muscles

there are Electric Organs

true

Muscular System Flashcards

(146 cards)