1. The Muscular System

2. Functions of the muscular system:. .
More than 600 muscles make up the system.
The muscular system is an organ system consisting of skeletal, smooth and cardiac muscles.
Attach to bones to provide movement.
Produce heat and energy for the body.
Maintain posture and body position.

3. Muscles get their energy from different sources depending on the situation that the muscle is working in. To keep muscles working for a longer period of time, muscle fibers contain several important energy molecules.

4. Energy for Muscle Contraction
Initially, muscles use stored ATP for energy
Bonds of ATP are broken to release energy
Only 4-6 seconds worth of ATP is stored by muscles
After this initial time, other pathways must be utilized to produce ATP
Slide 6.23
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

5. Muscle Fatigue and Oxygen Debt
When a muscle is fatigued, it is unable to contract
The common reason for muscle fatigue is oxygen debt
Oxygen must be “repaid” to tissue to remove oxygen debt
Oxygen is required to get rid of accumulated lactic acid
Increasing acidity (from lactic acid) and lack of ATP causes the muscle to contract less
Slide 6.27
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

6. Three Main Types of Muscles
Cardiac Muscles
These muscles form the walls of the heart and contract to circulate blood.
Visceral or Smooth Muscles
The visceral muscles are found in the internal organs of the body; they contract to cause movements in these organs.
Skeletal Muscles
- These attach to the bones of the body and cause body movement.
Visceral
Cardiac
Skeletal
Involuntary Movement
Voluntary Movement
NOT Striated
Striated Muscle Fibers
Nucleus
Intercalated Disks
&

7. Cardiac Muscle
Cardiac muscle (heart muscle) is an involuntary muscle that is found in the walls of the heart, the specific one is the myocardium. Cardiac muscle is only one of three major types of muscles. It is extremely important for your body. It is the only muscle that never stops working. It also does not get tired. Cardiac muscle tissue is extremely specialized. It is a type of muscle tissue that has the task of pumping blood throughout the body. The heart beats constantly and pumps blood throughout the body. It goes an entire lifetime without any rest. Cardiac muscle is extremely strong and has an incredible endurance. Due to the fact that the heart maintains its own rhythm, cardiac muscle has obtained the ability to swiftly spread electrochemical signals so that all of the cells in the heart can contract together as a whole.

8. Skeletal Muscle
Skeletal muscle is voluntary. It is the most common of the three types of muscle in the body. Skeletal muscles attach to bones by tendons. These muscles cause all of the body movements that correspond to each other. Unlike the other major types of muscles, skeletal muscle is voluntarily controlled. Skeletal muscles take up about 40% of the body’s total mass. It is long, thin, and has multinucleated fibers that are crossed with a regular pattern of fine red and white lines. Skeletal muscle fibers are together due to connective tissue. These muscles communicate with nerves and blood vessels.

9. Visceral (Smooth) Muscle
Visceral muscle tissue, or smooth muscle, is the tissue that is associated with the internal organs of the body, especially the ones in the abdominal cavity. The smooth, involuntary muscles of the visceral muscle tissue lines the blood vessels, stomach, digestive tract, and other internal organ. This muscle is composed of bundles of specialized cells. These cells contract and relax to create movement. The form of this muscle is in bundles. The primary and largest bundle is made up of muscle fibers where there are nerves, blood vessels, and connective tissue.

11. Muscle Properties:
Excitability: The ability to respond to a stimulus such as nerve impulse.
Contractibility: When muscle fibers that become stimulated by nerves they contract (causes movement)
Extensibility: The ability to be stretched.
Elasticity: The ability to have the muscle return to its original shape after movement.

12. Actions and movements performed by muscles:
Adduction: Moving a body part towards the midline.
Abduction: Moving a body part away from the midline.
Flexion: Decreasing the angle between two bones or bending a body part.
Extension: Increasing the angle between two bones.
Rotation: Turning a body part around its own axis.

13. Actions and movements performed by muscles:
-Circumduction: Moving in a circle at a joint.
-Pronation: Turning a body part downward.
-Supination: Turning a body part upward
-Dorsiflexion: Bending backward or bending the foot toward the knee.
-Plantar Flexion: Bending forward or bending the foot away from the knee.

14. Muscles and Body Movements
Movement is attained due to a muscle moving an attached bone
Muscles are attached to at least two points
Origin – attachment to a immoveable bone
Insertion – attachment to an movable bone
Figure 6.12
Slide 6.30b
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

15. Types of Muscles
Prime mover – muscle with the major responsibility for a certain movement
Antagonist – muscle that opposes or reverses a prime mover
Synergist – muscle that aids a prime mover in a movement and helps prevent rotation
Slide 6.35
Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

16. Muscular System Diseases:

17. Risk factors for myasthenia gravis include:
having a personal or family history of autoimmune diseases.
Men over 60 and women under 40 are at higher risk.
The most common 
symptoms are drooping eyes, double vision, difficulty chewing, choking on food, and muscle weakness.
Chronic condition where nerve impulses are not properly transmitted to the muscles creating abnormal weakness of certain muscles.
If the condition affects the respiratory muscles, it can be fatal.
It can affect any muscles that are under voluntary control. There is no cure for Myasthenia Gravis, but treatment can help relieve symptoms.
Myasthenia Gravis:

18. Myasthenia Gravis Symptoms and treatment
Symptoms: 1-Eyes are usually affected first. 2-Can affect mobility and breathing. Treatments: Pharmacologic therapy: Includes anticholinesterase medication and immunosuppressive agents. :
Myasthenia Gravis Symptoms and treatment

19. Fibromyalgia: Widespread muscle pain and tenderness.
More than 3 million US cases per year.
It’s a chronic disease, it can last for years or be lifelong.
Fibromyalgia is often accompanied by fatigue and altered sleep, memory and mood.
Medications, talk therapy and stress reduction may help control symptoms.
Fibromyalgia:

20. Fibromyalgia: What Causes Fibromyalgia?
Symptoms:
1- Pain in the muscles, abdomen, back or neck.
2-Fatigue, feeling tired or malaise.
3-Muscle soreness.
4-Sensitivity to cold.
5-Sleep disturbances.
6-Mood swings.
Treatments:
Therapies: Support group, Hydrotherapy, Stretching massage, and acupuncture.
Medication: Analgesic, Anti-inflammatory drug, Nerve pain medication and muscle relaxant.
What Causes Fibromyalgia?
Genes. Fibromyalgia seems to run in families.
Other diseases. A painful disease like arthritis or an infection raises your chances of getting fibromyalgia.
Emotional or physical abuse. ...
Posttraumatic stress disorder (PTSD). ...
Gender. Females more likely
Anxiety and depression. ...
Not moving enough.
Fibromyalgia:

21. A strain is an overstretched, torn, or twisted tendon or muscle.
A sprain is a stretching or tearing of ligaments. The most common location for a sprain is in your ankle.
The difference between a sprain and a strain is that a sprain injures the bands of tissue that connect two bones together, while a strain involves an injury to a muscle or to the band of tissue that attaches a muscle to a bone.
Symptoms:
Discoloration and bruising around the affected area.
Treatments:
Apply soft padding to minimize impact with objects.
-Rest
-Ice to reduce swelling
-Compression
-Elevation
Keep the area as close to the heart as is conveniently possible to keep blood from pooling in the injured area.
Strain versus Sprain:
Muscle spasms or cramps: sudden, painful, involuntary muscle contractions resulting from exertion, low electrolyte levels, or poor circulation

22. Shin Splints Description:
The term "shin splints" refers to pain and tenderness along or just behind the inner edge of the tibia, the large bone in the lower leg.
Shin splints--or medial tibial stress syndrome as it is called by orthopedists-- usually develops after physical activity, such as vigorous exercise or sports.
Repetitive activity leads to inflammation of the muscles, tendons, and periosteum (thin layer of tissue covering a bone) of the tibia, causing pain. The bone tissue itself is also involved.

23. Contracture
A contracture is a fixed tightening of muscle, tendons, ligaments, or skin. It prevents normal movement of the associated body part. An injury such as a severe burn can cause contracture of the skin. The skin becomes scarred and nonelastic which limits the range of movement of the affected area.

24. Muscle Atrophy

25. Tetanus is an infection caused by bacteria called Clostridium tetani.
When the bacteria invade the body, they produce a poison (toxin) that causes painful muscle contractions.
Another name for tetanus is “lockjaw”. It often causes a person’s neck and jaw muscles to lock, making it hard to open the mouth or swallow. 
Tetanus

26. DUCHENNE MUSCULAR DYSTROPHY
Symptoms may appear as early as infancy and include: Fatigue Muscle weakness which is worse in the legs  waddling gait Use of hands to raise self from floor Difficulty in running, jumping Frequent falling climbing stairs difficult Atrophy of muscles occurs with contractures and deformity Progressive difficulty in walking with ability to walk lost by 12 years of age Most patients at age 12 are confined to a wheelchair. Signs: A complete physical examination may show: Abnormal heart muscle (cardiomyopathy) Congestive heart failure  Deformities of the chest and back (scoliosis) Enlarged calf muscles which are later replaced by fat and connective tissue (pseudohypertrophy) Loss of muscle mass (wasting) Muscle deformities in the heels and legs Respiratory difficulty due to weakness of lung muscles
a genetic disease which causes rapid weakness and wasting of muscles.
males are more likely to develop symptoms than are women. 
occurs in 0.3 per cent of male infants in the population. 
DUCHENNE MUSCULAR DYSTROPHY

27. RICE: Rest, Ice, Compression, Elevation. Asthenia, asthen: Weakening.
Abbreviations:
AMB: Ambulate.
IM: Intramuscular.
RICE: Rest, Ice, Compression, Elevation.
Asthenia, asthen: Weakening.
Desis: To bind, tie together.

28. Ton/o: Tone, tension, or stretching. Flex/o: Bend. Plegia: Paralysis.
Word Parts:
My/o: Muscle
Ten/o: Tendon
Ton/o: Tone, tension, or stretching.
Flex/o: Bend.
Plegia: Paralysis.

29. Muscles & Functions

30. Location: On either side of the forehead.
Frontalis
Location: On either side of the forehead.
Function: Cover and protect the skull.

31. Location: Found over nasal bone.
Nasalis
Location: Found over nasal bone.
Function: Closes and opens the nasal openings.

32. Location: Corner of the mouth. Function: Raises corner of the mouth.
Zygomaticus Major
Location: Corner of the mouth.
Function: Raises corner of the mouth.

33. Function: Closes the eyelid.
Orbicularis Oculi
Location: Eye orbit.
Function: Closes the eyelid.

34. Trapezius
Location: Large triangular muscle located on the upper surface of the back.
Function: Moves the shoulder, extends the head.

35. Function: Flexes head, rotates head.
Sternocleidomastoid
Location: Large muscle extending diagonally down the sides of the neck.
Function: Flexes head, rotates head.

36. Location: Thick triangular muscle that corners the shoulder joint.
Deltoid
Location: Thick triangular muscle that corners the shoulder joint.
Function: Abducts the upper arm.

37. Location: Posterior arm to ulna. Function: Extends the lower arm.
Triceps Bronchii
Location: Posterior arm to ulna.
Function: Extends the lower arm.

38. Location: Part of the chest. Function: Flexes the upper arm.
Pectoralis Major
Location: Part of the chest. Function: Flexes the upper arm.

39. Location: upper arm radius. Function: Flexes the lower arm.
Biceps Brochii
Location: upper arm radius.
Function: Flexes the lower arm.

40. Rectus abdominis Location: Located in the front of the body.
Function: The muscle is activated while doing crunches because it pulls the ribs and pelvis in and curves the back.

41. External oblique
Location: Lateral and anterior sheet like abdominal muscles.
Function: Flexes vertebral column and compresses abdomen.

42. Internal Oblique Location: Abdominal muscles deep to external oblique.
Function: Bilateral contraction flexes vertebral column and compresses abdomen.

43. Location: Extends across the bottom of the thoracic cavity.
Diaphragm
Location: Extends across the bottom of the thoracic cavity.
Function: Responsible for breathing.

44. Sartorius Muscle
Location: Diagonal from anterior superior iliac spine to medial surface of tibia.
Function: Flexes leg and flexes abducts and rotates thigh.

45. Function: Flexes the foot and supports the heel.
Tibalis anterior
Location: Originates in the upper two thirds of the lateral surface of the tibia.
Function: Flexes the foot and supports the heel.

46. Location: Each sides of the hips. Function: Extends femur.
Gluteus Maximus:
Location: Each sides of the hips.
Function: Extends femur.

47. Gastrocnemius
Location: Calf muscle.
Function: Flexes the lower leg.

48. Soleus Location: A flat muscle that’s beneath the Gastrocnemius.
Function: Extends foot.

49. Calcaneal Location: Heel.
Function: This tendon connects the calf muscle to the heel bone.

50. Time for a Challenge…

51. What muscles are shown in the picture below?
(in red)

52. 2. Which types of major muscles are voluntary/involuntary? Name them

53. 3. What is one characteristic of cardiac muscle that differentiates it from any other muscle in the human body?

54. 4. What does Fibromyalgia cause?

55. 6. Name 1 property of a muscle.

56. 8. What does the abbreviation IM stand for?

57. 9. What are the 3 main functions of the muscular system ?

58. 10. Name the main cardiac muscle.

59. 11. What are skeletal muscles attached to?

60. 12. What is another word for visceral?

61. 13. What type of muscle is this picture depicting?

62. 14. How many types of major muscles are there? Name them.

63. 15. What attaches skeletal muscles to bones?

64. 16. What is 1 function of skeletal muscles?

65. 17. What muscle is highlighted in the picture below?

66. 18. Which major muscle group makes up about 40% of the body’s total mass?

67. 19. What is the main function of the diaphragm ?

68. 20. What does plegia mean?

69. The End