1. Muscles

2. What you Need to Know 1) Skeletal, 2) Smooth & 3) Cardiac Muscle
Look briefly at the Structure of:
1) Skeletal, 2) Smooth & 3) Cardiac Muscle
Naming, Identification, Functions
You are only responsible for the identification of ALL muscles which are on your Lab Packet
In general:
Generates force to move your bones
Propel body fluids & ingested food
Generate and distribute heat

3. Muscle
Specialized for contraction  movement of skeleton or internal organs
c) smooth
a) skeletal
b) cardiac

4. Skeletal Muscle
-generally attaches to bone causes movement of skeleton
Characteristics:
-long & unbranched, tightly packed, parallel cells
-multinucleated
-striated (striped)
-voluntary (conscious control)

5. Cardiac Muscle -muscle of the heart Characteristics:
-1 nucleus per cell
-branched cells with mild striations
-involuntary (not consciously controlled)

6. Smooth Muscle
-movement within internal organs other than the heart (e.g. digestive tract, bladder, arteries, etc.)
Characteristics:
-tapered cells
-single nucleus/cell
-no striations
-involuntary

7. Observe muscle slides! Use these pictures to quiz yourself!

8. Dense Regular Connective Tissue
-forms tendons (attach muscle to bone) and ligaments (attach bone to bone)
                        
-fibroblasts in collagen matrix
Collagen fibers
Fibroblasts

9. Facial Muscles p. 84 Frontalis: raises eyebrows; wrinkles forehead
Temporalis: elevates mandible
Orbicularis oculi: closes eye
Buccinator: compresses cheek
Orbicularis oris: closes and purses lips
Masseter: elevates mandible (closes jaw)

10. Facial Muscles Frontalis: raises eyebrows; wrinkles forehead
Temporalis: elevates mandible
Orbicularis oculi: closes eye
Orbicularis oris: closes and purses lips
Buccinator: compresses cheek
Masseter: elevates mandible (closes jaw)
No equivalent picture in lab manual

11. Sternocleidomastoid
-If both contracted flexion of head when both (nod down)
-If one contracted rotates head to opposite shoulder

12. Muscles Many muscles form antagonistic muscle pairs
Agonist: muscle that’s causing movement
Antagonist: muscle that opposes the agonist
An example…
During arm flexion:
Agonist:
Biceps brachii
Antagonist:
Triceps brachii
During arm extension:
Agonist:
Triceps brachii
Antagonist:
Biceps brachii

13. Muscles that Move Shoulder
Trapezius: elevates (i.e. raises shoulders) & retracts scapula (i.e. pulls shoulders back)
Elevates scapula
Retracts scapula

14. Muscles that Move Shoulder Draws scapula downward
No pic in lab manual
Pectoralis minor: draws scapula forward & downward (i.e. pulls shoulders down and forward)
Draws scapula forward
Draws scapula downward

15. Muscles that Move Shoulder
p. 82, 85
Muscles that Move Shoulder
Serratus anterior: draws scapula forward (i.e. pulls shoulder forward)
Serratus anterior
Draws scapula forward

16. Muscles that Move the Upper Arm
Pectoralis major: flexes (moves arm up and forward) & adducts upper arm (moves arm toward the body)
Flexes upper arm
Adducts upper arm

17. Muscles that Move the Upper Arm
Latissimus dorsi: extends (i.e. moves arm down to the rear) & adducts arm (moves arm toward body)
Extends upper arm
Adducts upper arm

18. Muscles that Move Upper Arm
Deltoid
Deltoid: abducts arm (raises arm up away from the side)
Abducts arm

19. Moving the Forearm Biceps brachii: flexes forearm
Brachialis: flexes forearm
Flexion of forearm
Biceps brachii
Brachialis
Biceps brachii
Brachialis

20. Muscles that Move the Forearm
p. 83, 85
Triceps brachii: extends the forearm
extension

21. Flexors & Extensors of Hand
Hand flexor group: flex the hand
p , 85
Hand extensor group: extend the hand p

22. Muscles of Abdominal Wall –Movement of Spine
Rectus abdominus: flexes vertebral column

23. Muscles of Abdominal –Moving the spine
Lateral flexion
External oblique: compresses abdomen; rotates trunk; lateral flexion
Trunk Rotation
Internal oblique: compresses abdomen; trunk rotation; lateral flexion
No pic
Compressing abdomen
Transversus abdominis: compresses abdomen
No pic

24. Muscles of Chest Wall –Movement of Ribs
Internal intercostals: depresses rib cage during forced expiration
External intercostals: elevates rib cage during inspiration
No pics
Diaphragm: prime mover during inspiration; increases vertical dimension of thorax

25. Muscles of Chest Wall –Movement of Ribs
Internal intercostal
External intercostal

26. Muscles that Move the Thigh
Gluteus maximus: extends thigh
p. 83, 86

27. Muscles that Move the Thigh
iliopsoas: flexion of thigh
Flexion of thigh

28. Muscles that Move the Thigh
Flexion of thigh
Tensor fascia latae: flexes & abducts thigh
Abducts of thigh

29. Muscles that Move the Thigh
Adductor group: adducts and flexes thigh
Adducts of thigh
Flexion of thigh

30. Muscles that Move the Thigh
sartorius: flexes & laterally rotates thigh; helps you sit cross-legged
Lateral rotation & flexion of thigh

31. Muscles that Move the Thigh
Knee extension
Quadriceps femoris group: extends knee
Rectus femoris: extends knees and flexes thigh
Flexion of thigh

32. Muscles that Move the Lower Leg
Extension of thigh
Hamstring group: extends thigh & flexes knee
Knee flexion

33. Muscles that Move the Foot
Tibialis anterior: dorisflexes foot
Gastrocnemius: plantar flexes foot, flexes knee
Soleus: plantar flexes foot

34. Today’s Activities Muscles: Tissue & Histology Muscles: Gross Anatomy
Examine the following slides using the microscope:
1) Skeletal muscle
3) Cardiac muscle
4) Dense regular connective tissue
2) Smooth muscle
Muscles: Gross Anatomy
Use the models and diagrams in you textbook & lab manual to study locations & actions of the muscles listed on pp
Diagrams in textbook = right side; most models = left side
Don’t worry about extra muscles described in textbook
Don’t worry about extra actions described in textbook
Answer questions, fill out diagrams on pp
If you get done early, you can go back to the bones, etc.
DO NOT leave until you have been excused, or you will be marked absent!!!

36. Medial View
Radial view
Medial View-Deep flexors
Lateral View
Lateral View-Deep extensors
Lateral View-Deep shoulder extensors

37. Anterior View
Posterior View
Lateral View
Medial View
Plantar surface

38. Search “MuscleandMotion” on YouTube