Muscular Tissue - Minia1)muscular... · 2020. 3. 16. · Muscular Tissue. Functions of Muscle...
Transcript of Muscular Tissue - Minia1)muscular... · 2020. 3. 16. · Muscular Tissue. Functions of Muscle...
Muscular TissueMuscular TissueMuscular TissueMuscular Tissue
Functions of MuscleFunctions of Muscle
Movement:Movement: skeletal,skeletal, cardiac, and smooth cardiac, and smooth musclesmuscles
Stability:Stability: skeletal muscleskeletal muscle
Communication:Communication: skeletal muscleskeletal muscleCommunication:Communication: skeletal muscleskeletal muscle
Control of body openings and passages:Control of body openings and passages:skeletal and smooth musclesskeletal and smooth muscles
Heat production:Heat production: skeletal musclesskeletal muscles
Functions of MuscleFunctions of Muscle
cardiac, and smooth cardiac, and smooth
skeletal muscleskeletal muscle
skeletal muscleskeletal muscleskeletal muscleskeletal muscle
Control of body openings and passages:Control of body openings and passages:skeletal and smooth musclesskeletal and smooth muscles
skeletal musclesskeletal muscles
Properties of MusclesProperties of Muscles
ExcitabilityExcitability ((responsiveness)responsiveness)chemical, mechanical or electrical stimuli.chemical, mechanical or electrical stimuli.
ConductivityConductivity initiate events that lead to initiate events that lead to contraction.contraction.
ContractilityContractility ability to shorten substantiallyability to shorten substantially
ExtensibilityExtensibility able to stretch between able to stretch between contractions.contractions.
ElasticityElasticity ability to return to original length ability to return to original length after stretching.after stretching.
Properties of MusclesProperties of Muscles
responsiveness)responsiveness) respond to respond to chemical, mechanical or electrical stimuli.chemical, mechanical or electrical stimuli.
initiate events that lead to initiate events that lead to
ability to shorten substantiallyability to shorten substantially
able to stretch between able to stretch between
ability to return to original length ability to return to original length
Muscle TissueMuscle TissueThere are There are 3 3 types of muscle tissue:types of muscle tissue: skeletalskeletal smoothsmooth cardiaccardiac
Muscle TissueMuscle Tissuetypes of muscle tissue:types of muscle tissue:
Classification of Muscle CellsClassification of Muscle Cells
Striated vs. Nonstriated Striated vs. Nonstriated
striated have a banded appearance (stripes)striated have a banded appearance (stripes)
Single nucleus or multinucleated cellsSingle nucleus or multinucleated cells
Muscle cells can be controlled Muscle cells can be controlled Muscle cells can be controlled Muscle cells can be controlled
voluntarily (consciously)voluntarily (consciously)
oror
involuntarilyinvoluntarily ((automatically)automatically)
Classification of Muscle CellsClassification of Muscle Cells
Striated vs. Nonstriated Striated vs. Nonstriated
striated have a banded appearance (stripes)striated have a banded appearance (stripes)
Single nucleus or multinucleated cellsSingle nucleus or multinucleated cells
Muscle cells can be controlled Muscle cells can be controlled Muscle cells can be controlled Muscle cells can be controlled
voluntarily (consciously)voluntarily (consciously)
automatically)automatically)
Skeletal MuscleSkeletal Muscle
Cells are long and cylindrical in shapeCells are long and cylindrical in shape
Cells are multiCells are multi--nucleatednucleated
CrossCross--striations presentstriations present
Under voluntary controlUnder voluntary control
Contractile proteins:Contractile proteins: actin, myosin and tinin.actin, myosin and tinin.Contractile proteins:Contractile proteins: actin, myosin and tinin.actin, myosin and tinin.
Regulatory proteins:Regulatory proteins: troponin and tropomyosin.troponin and tropomyosin.
Sarcomere is contractile unit of skeletal muscle; Sarcomere is contractile unit of skeletal muscle; defined as the distance between defined as the distance between
Skeletal MuscleSkeletal Muscle
Cells are long and cylindrical in shapeCells are long and cylindrical in shape
nucleatednucleated
striations presentstriations present
Under voluntary controlUnder voluntary control
actin, myosin and tinin.actin, myosin and tinin.actin, myosin and tinin.actin, myosin and tinin.
troponin and tropomyosin.troponin and tropomyosin.
Sarcomere is contractile unit of skeletal muscle; Sarcomere is contractile unit of skeletal muscle; defined as the distance between defined as the distance between 2 2 “Z” discs.“Z” discs.
Skeletal MuscleSkeletal MuscleWhole muscle Single muscle fiber
Skeletal MuscleSkeletal MuscleSingle muscle fiber
Skeletal Muscle Structure/ OrganizationSkeletal Muscle Structure/ OrganizationSkeletal Muscle Structure/ OrganizationSkeletal Muscle Structure/ Organization
Skeletal Muscle CellsSkeletal Muscle Cells
Striated, voluntary,Striated, voluntary, and multinucleatedand multinucleated
are long,are long, thin and cylindrical; they are thin and cylindrical; they are attached to bones and move our skeletonattached to bones and move our skeleton
are usually called “are usually called “muscle fibersmuscle fibers are usually called “are usually called “muscle fibersmuscle fibers
do not divide to create new cellsdo not divide to create new cells
new fibers are produced by stem cellsnew fibers are produced by stem cells
Striations Striations ---- cross stripes (bands) run cross stripes (bands) run perpendicular to the cellsperpendicular to the cells
Skeletal Muscle CellsSkeletal Muscle Cells
and multinucleatedand multinucleated
thin and cylindrical; they are thin and cylindrical; they are attached to bones and move our skeletonattached to bones and move our skeleton
muscle fibersmuscle fibers””muscle fibersmuscle fibers””
do not divide to create new cellsdo not divide to create new cells
new fibers are produced by stem cellsnew fibers are produced by stem cells
cross stripes (bands) run cross stripes (bands) run perpendicular to the cellsperpendicular to the cells
Skeletal Muscle TissueSkeletal Muscle TissueSkeletal Muscle TissueSkeletal Muscle Tissue
Neuromuscular controlNeuromuscular control
Skeletal muscle contraction is controlled by a nerve Skeletal muscle contraction is controlled by a nerve impulse (action potential) transmitted by the motor impulse (action potential) transmitted by the motor nerve from the brain or spinal cord.nerve from the brain or spinal cord.
motor unitmotor unit consists of all the muscle fibers controlled consists of all the muscle fibers controlled by a single motor neuron.by a single motor neuron.by a single motor neuron.by a single motor neuron.
Fine control muscles (i.e. eyelid muscles) have fewer Fine control muscles (i.e. eyelid muscles) have fewer muscle fibers/ nerve (muscle fibers/ nerve (22::11).).
A contraction is initiated by an action potential (nerve A contraction is initiated by an action potential (nerve impulse) and followed by the release a chemical impulse) and followed by the release a chemical neurotransmitter at the neuromuscular junction (NMJ). neurotransmitter at the neuromuscular junction (NMJ).
Neurotransmitter for skeletal muscle is acetylcholine.Neurotransmitter for skeletal muscle is acetylcholine.
Neuromuscular controlNeuromuscular control
Skeletal muscle contraction is controlled by a nerve Skeletal muscle contraction is controlled by a nerve impulse (action potential) transmitted by the motor impulse (action potential) transmitted by the motor nerve from the brain or spinal cord.nerve from the brain or spinal cord.
consists of all the muscle fibers controlled consists of all the muscle fibers controlled
Fine control muscles (i.e. eyelid muscles) have fewer Fine control muscles (i.e. eyelid muscles) have fewer
A contraction is initiated by an action potential (nerve A contraction is initiated by an action potential (nerve impulse) and followed by the release a chemical impulse) and followed by the release a chemical neurotransmitter at the neuromuscular junction (NMJ). neurotransmitter at the neuromuscular junction (NMJ).
Neurotransmitter for skeletal muscle is acetylcholine.Neurotransmitter for skeletal muscle is acetylcholine.
Neuromuscular controlNeuromuscular control
Each muscle fiber is innervated by a single Each muscle fiber is innervated by a single motor neuronmotor neuron
Contractions may be graded or full due to the Contractions may be graded or full due to the number of muscle fibers that respond to the number of muscle fibers that respond to the stimulus. The more fibers, the greater the stimulus. The more fibers, the greater the stimulus. The more fibers, the greater the stimulus. The more fibers, the greater the muscle contractionmuscle contraction
Synapse Synapse –– functional connection between a functional connection between a nerve fiber and its target cell.nerve fiber and its target cell.
Neuromuscular junctionNeuromuscular junctionmotor nerve and a muscle fiber.motor nerve and a muscle fiber.
Neuromuscular controlNeuromuscular control
Each muscle fiber is innervated by a single Each muscle fiber is innervated by a single
Contractions may be graded or full due to the Contractions may be graded or full due to the number of muscle fibers that respond to the number of muscle fibers that respond to the stimulus. The more fibers, the greater the stimulus. The more fibers, the greater the stimulus. The more fibers, the greater the stimulus. The more fibers, the greater the
functional connection between a functional connection between a nerve fiber and its target cell.nerve fiber and its target cell.
Neuromuscular junctionNeuromuscular junction –– synapse between a synapse between a motor nerve and a muscle fiber.motor nerve and a muscle fiber.
Every muscle contraction is preceded by a nerve impulse from Every muscle contraction is preceded by a nerve impulse from
the CNS.the CNS.
Motor nerve
Muscle fibersinnervated by innervated by single motorneuron
Neuromuscularjunctions
Every muscle contraction is preceded by a nerve impulse from Every muscle contraction is preceded by a nerve impulse from
Cardiac muscleCardiac muscle
Characterized by:Characterized by:
-- crosscross--
-- intercalated discsintercalated discs
-- uniuni--nucleate cellsnucleate cells-- uniuni--nucleate cellsnucleate cells
-- automaticityautomaticity
Composed of the same contractile proteins as Composed of the same contractile proteins as skeletal muscle.skeletal muscle.
Cardiac muscleCardiac muscle
Characterized by:Characterized by:
--striationsstriations
intercalated discsintercalated discs
nucleate cellsnucleate cellsnucleate cellsnucleate cells
automaticityautomaticity
Composed of the same contractile proteins as Composed of the same contractile proteins as skeletal muscle.skeletal muscle.
Cardiac Muscle CellsCardiac Muscle Cells
are called “are called “cardiocytescardiocytesheart wallsheart walls
branching cells connect at branching cells connect at disks disks which allow contractions to occur which allow contractions to occur fasterfaster
are regulated by pacemaker cells which are regulated by pacemaker cells which control contraction of the heart musclescontrol contraction of the heart muscles
striated, involuntary,striated, involuntary,
Cardiac Muscle CellsCardiac Muscle Cells
cardiocytescardiocytes” ” and found in and found in
branching cells connect at branching cells connect at intercalated intercalated which allow contractions to occur which allow contractions to occur
are regulated by pacemaker cells which are regulated by pacemaker cells which control contraction of the heart musclescontrol contraction of the heart muscles
striated, involuntary,striated, involuntary, and single nucleusand single nucleus
Cardiac muscleCardiac muscle
Characterized by:Characterized by:
-- crosscross--
-- intercalated discsintercalated discs
-- uniuni--nucleate cellsnucleate cells-- uniuni--nucleate cellsnucleate cells
-- automaticityautomaticity
Composed of the same contractile proteins as Composed of the same contractile proteins as skeletal muscle.skeletal muscle.
Cardiac muscleCardiac muscle
Characterized by:Characterized by:
--striationsstriations
intercalated discsintercalated discs
nucleate cellsnucleate cellsnucleate cellsnucleate cells
automaticityautomaticity
Composed of the same contractile proteins as Composed of the same contractile proteins as skeletal muscle.skeletal muscle.
Cardiac Muscle TissueCardiac Muscle TissueCardiac Muscle TissueCardiac Muscle Tissue
Smooth muscleSmooth muscle
Characterized by:Characterized by:
Spindle shaped cellsSpindle shaped cells
UniUni--nucleate cellsnucleate cells
Involuntary controlInvoluntary control Involuntary controlInvoluntary control
Found in walls of hollow organs, blood Found in walls of hollow organs, blood vessels and glandsvessels and glands
Smooth muscleSmooth muscle
Characterized by:Characterized by:
Spindle shaped cellsSpindle shaped cells
nucleate cellsnucleate cells
Involuntary controlInvoluntary controlInvoluntary controlInvoluntary control
Found in walls of hollow organs, blood Found in walls of hollow organs, blood vessels and glandsvessels and glands
Smooth Muscle CellsSmooth Muscle Cells are small and pointed at their endsare small and pointed at their ends
can divide and regenerate new cellscan divide and regenerate new cells
nonnon--striated, involuntary,striated, involuntary,
found in hollow organs like the intestine, found in hollow organs like the intestine, bladder, lungs, and blood vesselsbladder, lungs, and blood vesselsbladder, lungs, and blood vesselsbladder, lungs, and blood vessels
move substances through hollow opening move substances through hollow opening by contracting slowly; they squeeze things by contracting slowly; they squeeze things through like a tube of toothpastethrough like a tube of toothpaste
Smooth Muscle CellsSmooth Muscle Cellsare small and pointed at their endsare small and pointed at their ends
can divide and regenerate new cellscan divide and regenerate new cells
striated, involuntary,striated, involuntary, and single nucleusand single nucleus
found in hollow organs like the intestine, found in hollow organs like the intestine, bladder, lungs, and blood vesselsbladder, lungs, and blood vesselsbladder, lungs, and blood vesselsbladder, lungs, and blood vessels
move substances through hollow opening move substances through hollow opening by contracting slowly; they squeeze things by contracting slowly; they squeeze things through like a tube of toothpastethrough like a tube of toothpaste
Smooth Muscle TissueSmooth Muscle TissueSmooth Muscle TissueSmooth Muscle Tissue