1. The Muscular System
Unit 5

2. Unit Goals
Describe the functions and structures of the muscular system including muscle fibers, fascia, tendons, and the three types of muscle
Recognize, define, spell and pronounce the terms related to muscle movements and explain how the muscles are named.
Recognize, define, pronounce and spell the terms related to the pathology and diagnostic and treatment procedures of the muscular system*
Time Permitting

3. Enrichment Terms (see attachment)
antagonist- muscle that acts in opposition to the action of another muscle, its agonist
atrophy- wasting away, decrease in size
contraction- shortening or development of tension in muscle tissue
contracture- permanent shortening of tendons and ligaments of a joint resulting from atrophy of muscle
dystrophy- muscle disorder resulting from defective or faulty nutrition, abnormal development, infection
myalgia- muscle pain
paralysis- loss or impairment of motor function
posture- attitude or position of the body

4. Terms Cont.
prime mover- muscle that acts directly to bring about a desired movement, agonist
range of motion- active or passive movement of muscle groups to full extent possible, used to prevent contracture
sarcomere- repeating units of muscle fibers with the ability to contract
skeletal- pertaining to the framework of the body
stimulus- any agent, act, or influence that produces a change in the development or function of tissues
tonus- slight, continuous contraction of muscle
visceral- pertaining to any large interior organ in any one of the cavities of the body

5. What is a muscle? Contractile Tissue (group of cells working together)
Produces force and motion

6. Muscle Types Smooth Muscle: Automatically stimulated No striations
Found in digestive system, hair follicles, and reproductive system

7. Muscle Types Skeletal Muscle: Striated Voluntary
Found in face, limbs, torso
Line all the bones in the body

8. Muscle Types Cardiac Muscle Some striations
Stimulated by the vagus nerve in the brain
Found on in the heart
Specialized to carry and spread an electrical charge!

9. Types of Muscle Review

10. How does the muscle flex?
Muscle movement begins in the brain
Control of movement occurs in the primary motor cortex (M1)
Sends out nerve impulses to specific areas of skeletal muscle

11. “Excitation”
The site of interaction b/t a neuron and any other cell is known as a synapse.
The synapse b/t a neuron and a muscle is known as the neuromuscular junction.
Excitation causes a reaction involving Na+, K+, and Ca2+

12. Brain Movement Map

13. Muscle Action Terms
Flexion: decrease in joint angle from anatomical position (ex: bicep flex)
Extension: Return of body to anatomical pos. after flexion
Abduction: movement of limbs away from body (ex: jumping jacks/ snow angels)
Adduction: return of limbs back to anatomical pos. after abduction

14. More Terms
Inversion: turning soles of feet to face each other (ex: common ankle sprain)
Eversion: soles of feet turn laterally
Protraction: horizontal movement in anterior direction (ex: jutting jaw forward)
Retraction: return to regular from horizontal

15. More Terms
Elevation: To move in superior direction (ex: shoulder shrug)
Depression: move inferiorly (ex: drop shoulders)

16. Last Terms
Supination: lateral rotation of the hand (ex: palms down to palms up, as if holding a bowl of soup)
Pronation: medial rotation of the hands (ex:palms up to palms down, dribbling position)
Plantarflexion: increasing the angle b/t the shin and top of foot (ex: stand on toes)
Dorsiflexion: decreasing the angle b/t the shin and top of foot
REVIEW TOGETHER

17. Sample Movements- Hand

18. Muscular System There are over 600 muscles Functions include: Movement
Posture Maintenance
Generation of Heat
Breathing/ Digestion (compression of abdomen)

19. Individual Muscle Groups- Shoulder and Arm
Trapezius: Extends/abducts head, rotates scapula
Deltoid: Abducts arm, flexes, extends, rotates (delts)
Pectoralis Major: Flexes, adducts arm (pecs)
Latissimus Dorsi: Extends, adducts arm (lats)
Biceps Brachii: Flexes arm, supinates hand (bis)
Triceps Brachii: Extends, adducts arm (tris)
Individual Muscle Groups- Shoulder and Arm

20. Shoulder and Arm

21. Individual Muscle Groups- Hip and Thigh
Sartorius: Flexes and Laterally rotates thigh
Quadriceps: (grp of 4) Extend leg, flex thigh (Rectus Femoris, Vastus Lateralus/Medialis)
Hamstring Group: Extend thigh/ flex leg
(Biceps Femoris)

24. Individual Muscle Groups- Leg and Foot
Gastrocnemius: flex leg/ plantarflexes foot (also known as the calf muscle)
Soleus: Plantar flexes foot
Tibialis anterior: inverts foot/dorsiflexes foot

25. Individual Muscle Groups- Head and Neck
Masseter: Closes mandible, largest mammalian mandible found on the rat
Zygomaticus: elevates the corners of the mouth, attached at zygomatic bone, responsible for your smile!
(Sternocleidomastoid, Orbicularius oculi/oris)

27. Individual Muscle Groups Trunk
External Oblique: Compresses abdominal wall, laterally rotates trunk (love handles)
Transverse Abdominis: same fxn
Rectus Abdominis: Flexes vertebral column, compresses abdominal wall
External intercostals: Elevates ribs (increase volume)
Internal intercostals: Depresses ribs (decreases volume)

30. How Muscles Work