A&P 1 Module 04 Muscle Phys PPT.pptx - Muscle: Microscopic...

Muscle:
Microscopic Level
Muscle Tissue
Sliding Filament Theory
Fiber Types / Metabolism

Muscle Tissue
Anatomy and Physiology I

Objectives
11/21/2021
3
•
Describe the functions of the muscular system
•
Identify the special characteristics of muscle cells
•
Compare and contrast the three types of muscular tissue
•
Identify the gross anatomy of a muscle
•
Identify and describe the anatomical parts to the microscopic
observation of skeletal muscle tissue
•
Compare and contrast the thick and thin filament anatomy
•
Describe the anatomy and function of the neuromuscular
junction

Muscular System: Functions
•
Movement of bones and fluids (e.g., blood)
•
Maintaining posture and body position
•
Stabilization joints
•
Heat generation (especially skeletal muscle)
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4

Muscle Tissue: Characteristics
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Excitability: ability to receive and respond to stimuli
•
Contractility: ability to shorten when stimulated
•
Extensibility: ability to be stretched
•
Elasticity: ability to recoil to resting length
11/21/2021
5

Muscle Tissue: Categories
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Skeletal Muscle
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Attached to the skeletal system
–
Striated appearance and under voluntary control
•
Cardiac Muscle
–
Found in the heart
–
Striated appearance and under unconscious/involuntary
control
•
Smooth Muscle
–
Found primarily within internal organs
–
Not striated and under unconscious/involuntary control
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6

Muscle Tissue: Categories
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7
Skeletal Muscle
Smooth Muscle Cardiac Muscle

Skeletal Muscle Anatomy
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Tendon
•
Fascia
•
Epimysium
•
Perimysium
•
Fascicles
•
Endomysium
•
Muscle cell (fiber)
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8

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9

Skeletal Tissue: Overview
•
Muscle cell and muscle fiber used interchangeable
•
To understand muscle physiology, vital to understand
muscle anatomy
•
Muscle fibers are long cylindrical shaped cells
–
Have multiple nuclei
–
Majority of cell filled with myofibrils (protein filaments)
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10

Skeletal Muscle Fiber
•
Sarcolemma
•
Sarcoplasmic
reticulum
•
Nuclei
•
Mitochondria
•
T-tubules
•
Myofibrils
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11

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12

Skeletal Muscle Fiber
•
Myofibrils contain
specialized proteins
referred to as
myofilaments:
–
Thick filament
–
Thin filament
•
Arranged in
SACROMERES
–
Unique arrangement
to allow for muscle
contraction to occur
11/21/2021
13

Skeletal Muscle Fiber
•
Sarcomere
–
From Z line to Z line
–
Arrangement of
thick and thin
filaments
–
Causes striated
appearance
–
Contractile unit of
muscle
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14

Sarcomere
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15

Skeletal Muscle Fiber: Thick Filament
•