1. Anatomy-Muscular System
Muscle Types, Characteristics & Function

2. Bell Work Grab your note taker from the front table
Discuss in your groups the anatomical movements at each joint
Be ready to demonstrate different anatomical movements!

3. Objectives Students will be able to:
Define terms for muscle types & characteristics
Identify muscle types, characteristics & function
Label & give examples of muscle types
Compare muscle response to USE and DISUSE
List skeletal muscle contractions & response to stimulus

4. Terminology Striated Striped Voluntary
Metric
Length of muscle
Myo
Muscle
Tendon
Connects muscle to bone
Contraction
Shortening or tensing of a muscle
Striated
Striped
Voluntary
Conscious control by will/choice
Involuntary
Not under conscious control

5. General Characteristics
Muscles provide ACTION for the body
Excitable
Muscles are electrically excitable
Action occurs when nerve cell stimulates the muscle cell
Contractable
Muscle cells contract
Shorten or tense

6. General Characteristics
Extensible
Ability to stretch from the normal resting length
Elastic
Ability to return from a stretch to normal resting length

7. Muscle Types-Smooth Characteristics
Occurs in layers in walls of hollow internal organs
Blood vessels, digestive system, urinary system & other internal organs
Involuntary

8. Muscle Types-Smooth Structure Elongated cells with tapered ends
Not striated
Shorter than skeletal muscle cells

9. Anatomy-Muscular System Muscle Types-Smooth
Function
Slower to contract & relax
Can maintain longer contraction (endurance)
Wave like contractions

10. Muscle Types-Smooth
Smooth Muscle Cells
Microscope View
Stained

11. Muscle Types-Smooth Myofibrils Contractile part of muscle fiber
Nucleus
Hereditary material, controls metabolism
Sarcoplasm
Protein to control cell metabolism
Cell Membrane
Surrounds cell
Myofibrils
Nucleus
Sarcoplasm
Cell Membrane

12. Muscle Types-Cardiac Characteristics Occurs only in the heart
Involuntary

13. Muscle Types-Cardiac Structure Striated cells joined end to end
Cells interconnected in branching networks
Intercalated disks between cells to hold cells together

14. Muscle Types-Cardiac Function Capable of long contractions
Has strength & appearance of skeletal muscle
Has endurance of smooth muscle

15. Muscle Types-Cardiac
Cardiac Muscle Cells
Microscope View
Stained

16. Muscle Types-Cardiac Striations Stripes Intercalated Disks
Branch
Striations
Stripes
Intercalated Disks
Separate cells & hold cell together
Nucleus
Contains hereditary material & controls cell metabolism
Nucleus
Intercaladed Disks

17. Muscle Types-Skeletal
Characteristics
Attached to bone by a tendon
Function together with bones to provides movement
Voluntary

18. Muscle Types-Skeletal
Structure
Striated
Cylindrical shape with rounded ends
Covered by loose connective tissue called “fascia”

19. Muscle Types-Skeletal
Function
Contraction occurs when muscle cell is stimulated by an electro-chemical impulse from a nerve
Muscle contracts & moves body part

20. Muscle Types-Skeletal
Skeletal Muscle Cells
Microscopic View
Stained

21. Muscle Types-Skeletal
Epimysium
Connective tissue surrounding muscle
Perimysium
Connective tissue surrounding bundle of fibers
Endomysium
Connective tissue surrounding muscle fiber
Blood Vessel
Perimysium
Endomysium
Epimysium
Bone
Tendon

22. Muscle Types-Skeletal
Fascicle
Small bundle
Muscle fiber
Elongated contractile cell
Muscle Fiber
Fascicle
Blood Vessel
Endomysium
Perimysium
Epimysium
Bone
Tendon

23. Skeletal Muscle Response to Use Hypertrophy
Increase in muscle fiber size
Not in # muscle fibers
More forceful contraction

24. Skeletal Muscle Response to Disuse Atrophy
Decrease in muscle fiber size
Not in # muscle fibers
Less forceful contraction

25. What does that mean?
Contraction strength directly related to diameter of muscle fiber
The BIGGER the muscle fiber – the more you have used that muscle
The SMALLER the fiber – the Less you have used that muscle

26. 3 Types of Muscle Contractions
Isometric
Muscle contracts but does not shorten
Concentric
Muscle shortens during contraction
Eccentric
Muscle lengthens during contraction

27. Muscle Response Threshold Response
Minimal strength of stimulus to get a contraction
Muscle remains unresponsive until a certain strength of stimulus is applied

28. Muscle Response 2. All-or-None Response
Muscle fibers are completely relaxed or contracted
Stimulus must be threshold strength or greater to get a contraction
No Partial Contraction
of muscle fibers
Either you contract or you don’t!

29. Muscle Types-Skeletal

30. Wrap it up… On a sheet of paper… List an example of Smooth muscle
Cardiac muscle
Skeletal muscle
AND give me
One characteristic
Its structure
One function
TURN IN ONCE YOU ARE FINISHED!
Example:
Smooth muscle (give example)
Characteristic
Structure
Function