Download presentation
Presentation is loading. Please wait.
1
The Muscular System Labs 7 & 8
2
In Lab today: Draw the muscle types & indicated structures from prepared slides Identify the portions of skeletal muscle from diagrams, slides and models Identify the connective tissue coverings associated with skeletal muscle Draw the neuromuscular junction from a prepared slide & identify the indicated structures Identify the human muscles from models and diagrams Study models and diagrams in preparation for the muscle quiz in 2 weeks
3
Objective 1 Types of Muscle Tissue
4
Location Structure Function
Skeletal Muscle Location Structure Function Attached to the Long, thin cells (fibers) are: posture, movement, skeleton - striated stabilizes joints - multinucleated nuclei are in the periphery of the cell The plasma membrane of the muscle fiber
5
Striations of the myofibrils are seen through the muscle fiber
6
Striations: A bands & I bands
(dark bands) (light bands)
7
A-bands, I-bands, Sarcomeres, & Sarcolemma
8
Skeletal Muscle Note multi-nucleation Whole mount, oil immersion
9
Skeletal Muscle Nuclei A-band I-band Sarcomere Sarcolemma
Note nuclei on the periphery of the cells (fibers) Nuclei A-band I-band Sarcomere Sarcolemma Longitudinal section, oil immersion
10
CARDIAC MUSCLE
11
The heart muscle (myocardium) forms the bulk of the heart.
It is arranged in a spiral or circular bundles. Cardiac muscle bundles “Helical heart” model
12
CARDIAC MUSCLE
13
Intercalated Disc Nucleus Cardiac Muscle Location Structure Function
Wall of the heart Cells (myocytes) are: provide pressure - faintly striated for the circulation - branching of blood with one (or two) centrally placed nuclei Cells are connected by intercalated discs (gap junctions/desmosomes) Intercalated Disc Nucleus
14
Cardiac Muscle Branching cells are in 3-D;
may not be particularly visible in 2-D Central nuclei Intercalated disk
15
Cardiac Muscle Central nuclei Intercalated disk
16
Cardiac Muscle Intercalated discs
17
SMOOTH MUSCLE
18
Smooth muscle is found in the walls of hollow visceral organs.
Contractions force fluids and other substances along. Cells are arranged closely to form sheets. Epithelial Tissue C.T. C.T. Connective Tissue E.T. E.T. C. T. Epithelial Tissue
19
Location Structure Function
Smooth Muscle Location Structure Function Walls of hollow Cells are: move fluids organs - spindle shaped and other contents - have a single nucleus - not striated nucleus
20
How you might see it under High Power
Smooth Muscle How you might see it under High Power
21
How you might see it under Oil Immersion
Smooth Muscle How you might see it under Oil Immersion
22
REVIEW Skeletal muscle Cardiac muscle Smooth muscle
23
Objective 2 Connective Tissue Coverings of Skeletal Muscle
24
Note that the endomysium surrounds the sarcolemma
25
Cross section through a skeletal muscle
Epimysium Perimysium Endomysium / muscle fiber
26
Skeletal Muscle, cs & ls A muscle fiber is filled with myofibrils
Nuclei
27
Cross section through a skeletal muscle
endomysium Magnified image
28
Epimysium Perimysium / Fascicle Endomysium / muscle fiber
29
Objective 3 Neuromuscular Junction
30
Reflex Arc N-M junction (Myoneural junction)
31
Neuromuscular Junction
Axon terminal Motor Neuron Axon Skeletal muscle fiber
32
Neuromuscular Junction
as you will see it under the microscope Skeletal muscle fiber Skeletal muscle fiber Motor Neuron Axon Axon Terminal
33
Neuron Axon Skeletal muscle fiber Axon Terminal
34
Muscles Origin, Insertion, Action, Innervation
35
The immovable (or less moveable) bone to which the muscle is attached
Origin The immovable (or less moveable) bone to which the muscle is attached Scapula Biceps brachii
36
Insertion The movable bone to which the muscle is attached
(The bone that the muscle moves) Radius Biceps brachii
37
Joint movement(s) caused by contraction of the muscle
Flexes and supinates forearm
38
The nerve that acts on the muscle
Innervation The nerve that acts on the muscle Musculocutaneous
39
Muscular System Click here
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.