lec08_musc (1). class presentation notes
- 1. Anatomy of muscular system Lecture 8
- 2. OBJECTIVES: By the end of this lecture, student should understand: • Characteristics of Muscle Tissue • Types of muscles • Nomenclature of muscles
- 4. 4 Characteristics of Muscle Tissue ❖Excitability :ability to receive and respond to stimuli ❖Contractility : ability to shorten and thicken ❖Extensibility : ability to stretch ❖Elasticity : ability to return to the original shape
- 5. Functions • Movement – both voluntary & involuntary ▪ Maintaining posture ▪ Control of body openings and passages. ▪ Production of body heat
- 6. The Muscular System •Three basic muscle types are found in the body: –Skeletal muscle –Cardiac muscle –Smooth muscle
- 7. Skeletal Muscles Skeletal muscles are • Voluntary, • Connected to bones, • Responsible for body movement
- 8. Skeletal Muscle Characteristics • Cells are multinucleate • Striated – have visible banding • Voluntary – subject to conscious control
- 9. Function of Skeletal Muscles • Produce movement • Maintain posture • Stabilize joints • Generate heat • Protect internal organs
- 10. • An average adult male is made up of 42% of skeletal muscle and • an average adult female is made up of 36% of skeletal muscle (as a percentage of body mass)
- 11. ❖The function of skeletal muscle is to contract to move parts of the body closer to the bone that the muscle is attached to.
- 12. Muscles and Body Movements Movement is attained due to a muscle moving an attached bone
- 13. Muscles and Body Movements • Muscles are attached to at least two points – Origin –the end of the muscle attached to a bone that doesn’t move – Insertion – the end of the muscle that attaches to a bone that moves
- 14. Muscles work in pairs. • Because muscle cells can only contract, not extend, skeletal muscles must work in pairs.
- 15. Muscles work in pairs. • While one muscle contracts, the other muscle in the pair relaxes.
- 16. Muscles work in pairs. • Flexors bend parts of your body. • Extensors straighten parts of your body.
- 17. Smooth Muscle • Smooth muscle is involuntary, found in the digestive tract, and helps to move food and materials through your body.
- 18. or "involuntary muscle" • Location – in the walls of internal organs such as the esophagus, stomach, intestines, bronchi, uterus, bladder, and blood vessels. • Involuntary: Unlike skeletal muscle, smooth muscle is not under conscious control.
- 19. Smooth Muscle Characteristics • Has no striations - smooth • Spindle-shaped cells • Single nucleus • contractions are slow
- 20. Cardiac Muscle • Cardiac muscle is involuntary and only found in the heart. Video Notes Anatomy Muscular System Smooth and Cardiac Muscle
- 21. Cardiac muscle (myocardium), is also an "involuntary muscle" but is more akin in structure to skeletal muscle, and is found only in the heart.
- 22. Cardiac Muscle Characteristics • Has striations • Usually has a single nucleus • Branched fibers • Joined to another muscle cell at an intercalated disc • Involuntary • Found only in the heart
- 23. 23 Cardiac Muscle • Heart muscle, • Involuntary • Striated (Similar to skeletal muscles) • Functions – Move blood through the heart and through the vessels
- 25. • 1. Adduction: moving a body part toward the midline • 2. Abduction: moving a body part away from the midline
- 26. Flexion/ Extension • 3.Flexion (Flexor) : decreasing the angle between two bones or the bending of a body part • 4. Extension (Extensor) : increasing the angle between two bones or straightening of a body part
- 27. Rotation • 5. Rotation: a circular motion which turns a body part on its axis
- 28. Supination and Pronation • Supination: the act of rotating the arm so the palm of the hand is upward. • Pronation: the act of rotating the arm so the palm of the hand is turned downward.
- 29. Depression and Elevation • Depression: to lower a part of the body • Elevation : to lift a part of the body
- 30. Connect Moving a body part toward the midline Moving a body part away from the midline
- 31. Fill in the space ………………………… ………………………….. …………………………..
- 32. Enumerate three types of muscular tissue 1. …………………………….. 2. …………………………….. 3. ……………………………..
- 33. Moving a body part toward the midline is called _________? A. Adduction B. Abduction C. Supination D. Extension
- 34. The act of rotating the arm so the palm of the hand is upward is called _________? A. Adduction B. Abduction C. Supination D. Extension
- 35. Decreasing the angle between two bones or the bending of a body part is called ______? A. Adduction B. Abduction C. Supination D. Extension E. Flexion
- 36. Cardiac muscles are ____ A. Voluntary striated B. Involuntary smooth C. Involuntary striated D. Voluntary smooth
- 37. The end of the muscle attached to a bone that doesn’t move is called _______? A. Origin B. Extension C. Insertion D. Target
- 38. The ability of muscles to shorten and thicken is called _____? A. Excitability B. Contractility C. Extensibility D. Elasticity
- 39. The ability of muscles to return to the original shape is called ____? A. Excitability B. Contractility C. Extensibility D. Elasticity
- 40. Type of muscles found in the digestive tract that helps to move food and materials through your body is ____? A. Smooth muscles B. Cardiac muscles C. Skeletal muscles
- 41. The following are true about Skeletal muscles, EXCEPT _____? A. Voluntary muscles B. Striated muscles C. Has a single nucleus D. Found connected to bones
- 42. The following are true about Cardiac muscles, EXCEPT _____? A. Voluntary muscles B. Striated muscles C. Has a single nucleus D. Branched fibers
- 43. The following is true about smooth muscles EXCEPT _____? A. Slow contractions B. Not striated C. Has a single nucleus D. Found connected to bones
- 44. Thank you