2. Skeletal System Osteology – the study/science of bones Human Skeleton
comprised of approximately 206 bones
at birth approximate 270
change due to fusion of separate bones during early growth
divided into axial and appendicular
Axial
skull 22 bones
ear ossicles 6
vertebrae 26
hyoid 1
rib cage 25

3. Appendicular
pectoral girdle 4 bones
upper extremities 60
pelvic girdle 2
lower extremities 60
**overhead and hand-out skeletal system

4. Functions of the Skeleton
five functions of the human skeleton
Support
forms rigid framework to which the softer tissues and organs of the body are attached
Protection
skull and vertebral column enclose central nervous system (CNS)
rib cage protects heart, lungs, liver spleen
pelvic girdle protects pelvic viscera
even RBC production factory protected within each individual bone

5. Body Movement
serve as anchoring attachments for most skeletal muscles
act as levers
Hemopoiesis
red bone marrow produces WBC, RBC, and platelets
approximately 1,000,000 red blood cells/second produced here
Mineral Storage
primarily calcium and phosphorus
95% of these minerals found in bones and teeth

6. Calcium
important in muscle contraction
blood clotting
ion movement across the cell
Phosphorus
activities of nucleic acids (DNA/RNA)
ATP utilization

7. AXIAL SKELETON
SKULL
8 bones
joined rigidly
protect brain and sense organs
FACIAL BONES
framework for facial regoin and support of teeth
HYOID BONE
supports tongue, and assists in swallowing
EAR OSSICLES (malleus, incus and stapes)
transfer and amplify sound impulses to middle ear

8. VERTEBRAE (vertebral column)
enclose and protect spinal cord
support and permit movement of skull
provide attachment for trunk muscles
RIB CAGE
directly involved in mechanics of breathing
protect vital organs
APPENDICULAR SKELETON
PECTORAL GIRDLE
Clavicle and Scapula
serves as attachment for numerous muscles involved in movement of arms

9. BRACHIUM
Humerous
anatomically defined as the upper arm
humerous is the only bone
FOREARM
Ulna and raduis
ulna is the larger of the two bones in lower arm
radius is the small bone, it is located on the thumb side and is responsible for articulation of arm and wrist

10. WRIST AND HAND
27 bones
Carpus
heel of hand
Metacarpus
flat of hand
Phalanges
fingers
PELVIC GIRDLE
Os coxae and symphysis pubis
support weight of upper body
protects and supports urinary bladder, reproductive organs, and developing fetus
shape of girdle differs in sexes

11. THIGH
Femur
femur is the only lone bone in the thigh
longest, heaviest and strongest bone in the body
major center for blood cell production and mineral storage
Patella
protects the knee joint
also referred to as the “knee cap”
LOWER LEG
Tibia
larger of the two bones in the lower leg
found on medial side of the leg
bears weight of the entire body

12. Fibula
small of the two lower leg bones
important for muscle attachment as opposed to support
Ankle
26 bones
Tarsus
heel of the foot
Metarsus
arch of the foot
Phalanges
toes and distal flat portion of the foot

13. JOINTS
The extent and type of movement determine the name applied to a joint. Bone structure limits the kind and amount of movement in each joint. Some joints are very limited whereas others have a variety of movement ranges.
articulate
the interaction between two or more bones, i.e. Bones moving together
flexibility
elasticity of the muscle tissue and tissue surrounding joints
Types of Joints
diarthrotic joints (majority of joints in the body)
suture joints (found in skull and pelvic area)
disc joints (found in vertebral column)

14. DIARTHROTIC JOINT GROUPS
Gliding Joint
two plane or flat bony surfaces that butt against each other, permitting limited gliding movement
e.g. Carpal bones of the wrist
Biaxial Ball and Socket Joints
the bones permit movement in two planes, without rotation
e.g. Wrist between the radius and the proximal row of the carpal bones
Multiaxial Ball and Socket Joints
permits movement in all planes
e.g. Shoulder and hip joints

15. Hinge Joints
permits a wide range of movement in only one place
e.g. Elbow, ankle, knee joints
Saddle Joint
reciprocal reception is found only in the thumb at the carpometacarpal joint and permits ball and socket movements with the exception of rotation
Pivot Joint
rotational movement around the long axis 18
e.g. Rotation (pronation/suppination) of the radius at the radiolnar joint
See page for handout

16. Joint Disorders
Injuries
dislocation
hyperextension
capsule tears
ligament tear
bone fracture
meniscus or cartilage damage
Osteomylithis
infection due to bacteria or virus following an injury

17. Osteoarthritis
due to aging/irritation, abrasion
no known cure
Rheumatoid Arthritis
sever pain
affects women 3:1 over men
synovial membrane becomes swollen and inflamed
deformity → cartillage turns to calcium deposit
Demineralization
due to lack of Vitamin D, aging and hormonal changes
astronauts often obtain this disorder
Gout
usually in the feet, especially big toe

18. Muscular System
Myology
the science/study of muscles
Muscles
contract when stimulated by electrical impulses
only have power when contracting → cannot push

19. Functions of the Muscular System
three functions of the muscular system
Motion
skeletal movement
breathing
movement of body fluids
cardiac movement moves blood
Heat Production
muscles constitute approximately 40% of the body’s weight
the continuous fiber activity is important in producing heat in the body
Posture and Support
maintain posture/offer support around joints
certain skeletal muscles even work without really knowing it
e.g. neck/head

20. all muscles are:
irritable → respond to stimulus
contractible → works by shortening
extensible → can be returned by opposing force
elastic → can be stretched and returned to original length
Over 600 skeletal muscles in the body (most are paired)
the names suggest where the muscle is located

21. TYPES OF MUSCLES
Smooth Muscle
involuntary, include blood vessels, intestines and lungs
Striated/Skeletal Muscle
responsible for the voluntary movement of the body
Cardiac Muscle
only one in body, the heart

23. Muscle System Actions Origin – where the muscle meets the bone that doesn’t move Insertion – where the muscle meets the bone that moves Flexors – muscle that bends joints pulls limbs towards body Extensors – straighten joints Agonist – prime mover → initiates the action Antagonist – relaxes or yields to agonist muscle Synergists – fixators → hold limb/joint steady during the action Hand-out diagrams of Muscle Types

24. FACIAL
Frontalis → over frontal bone (eyebrow movement)
Orbicularis occuli → surrounds the eyes (blinking)
Masseter → opens mouth
Temporalis → closes mouth
Zygomaticus → elevates the corner of the mouth (smiling)
Sternocleidomastoid → turns head
ABDOMINAL
External oblique, rectus abdominus, internal oblique, transverse abdominus
aid in breathing, defecation, and stabilize spine while lifting

25. PECTORAL GIRDLE
Front
Pectoralis major → adduct, flexes and rotates the brachium medially
Serratus anterior → pulls scapula forward and down
Back
Trapezius → adducts, elevates scapula
→ hyperextends the head
Latissimus dorsi →adducts arm, drawing it downward and back ward
Brachia and Forearm
Deltoid →abduct, extend and flex brachium
Bicep brachi → two heads, flexes forearm
Brachialis → works with bicep to flex forearm
Brachioradialis → flexes forearm

26. Tricep brachi → three heads, extends forearm
Legs
Gracilis, adductor longus, adductor magnus → adduct thigh and flex leg
Sartorius → longest muscle in the body
→crosses legs
Quadricep femoris → four muscles in this group
→ rectus femoris, vastus lateralis, vastus medialis, vastusintermedius
→ extend legs

27. Hamstrings → three muscles in this group → bicep femoris, semitendinosus, semimembranosus → flexion of leg at the knee Tibialis anterior → dorsi flexes the foot Peroneous Longus → plantar flexes the foot and eversion of foot Gastrocnemius → flexes knee, plantar flexes foot Soleus → plantar flexion of the foot

32. Textbook
p.40 Sliding Theory of Muscle Contraction
p.41 Diagrams – reproduce and understand
p.43 Reproduce

33. Sliding Filament Theory of Contraction
stimulated muscle contracts as a result of the shortening of its individual fibres
shortening of these fibres is accomplished in turn by the shortening of their own myofbrils
which is actually the shortening of distance between “z” lines
the thick myosin and thin actin filaments remain the same length during contraction
→ instead, the think “slide” over the thick

34. MUSCLE TISSUE STRUCTURE Epimysium – a fibrous outer sheath of connective tissue surrounding a skeletal muscle Perimysium – fascia (connective tissue) surrounding a bundle of muscle fibres Endomysium – the connective tissue sheath the surrounds each skeletal muscle fibre, separating the muscle cell from one another Fasciculi – a small bundle of muscles or nerve fibres MUSCLE CELL STRUCTURE Sarcolemma – the cell membrane of a muscle fibre Sarcoplasm – the cytoplasm within a muscle fibre Myofibrils – a bundle of contractile fibres within a muscle cell (thick and thin)

35. SARCOMERE STRUCTURE
Sarcomere – the portion of a striated muscle fibre between the two adjacent “Z” lines that is considered the functional unit of a myofibril
Myosin – “A” band – contain thick myofibrils – dark in appearance
Actin – “I” band – contain thin myofibrils – light in appearance
Z line – thin, dark center of each i-band. Basic sub-unit of striated muscle contraction
Cross-bridge – sliding of the myofibrils produced by the action of cross-bridges that extend from the myosin toward the actin
pull actin from each side toward the middle of the cell
extend from the axis of the thick myofilaments to form “arms” that terminate in globular heads
Isotonic Contraction – the force of contraction remains relatively constant throughout the shortening process

36. CIRCULATORY SYSTEM
Three functions of the circulatory system
Transport
respiratory – O2 and CO2
nutritional – absorbs products through liver
excretory – waste processed through kidneys
Regulation
hormones carried to target tissues
Protection
clotting mechanisms
leukocytes (WBC) attack disease

37. HEART
four-chambered, muscular organ
located in chest with 2/3 of the heart left of the midline with the point downward
upper right and left atria contract simultaneously and empty into ventricles
lower right and left ventricles also contract in synch to empty heart
Right Atrium
collects venous blood from superior vena cava (upper body) and inferior vena cava (lower body)

38. Left Atrium
received oxygenated blood from lungs through pulmonary veins (two from each lung)
Right Ventricle
right atrial blood enters via tricuspid and is pumped to lungs through pulmonary arteries
Left Ventricle
blood from left atrium enters via bicuspid valve
O2 blood leaves here via ascending aorta

39. Cardiac Cycle
contraction phase – systole, the “lub”
relaxation phase – diastole, the “dub”
3/8 of time is spend in the “dub” phase
above applies to ventricles, opposite is true for atrial systole and diastole
Blood Vessels
blood leaving heart passes through vessels
these vessels diminish in size as they go
arteries-arterioles-capillaries

41. Arteries
very elastic – stretch with the hearts contraction
carry oxygen rich blood
Capillaries
“functional units” of the circulatory system
gas and nutrient exchange takes place here
Veins
low pressure is insufficient to return blood to heart without venous valves

42. Venules
performs similar function as capillaries
Cardiac Output
measured in mL/min.=stroke vol/mL/beat X cardiac rat (beats/min)
average stroke volume=70-80mL/beat
average cardiac rate= 70 beats/min

45. RESPIRATORY SYSTEM
Three functions of the respiratory system are all similar
Ventilation
breathing
Gas exchange
oxygen and carbon dioxide transfer in lungs
O2 utilization

46. Major Passages
Nasal Cavity – Nose
warms, moistens and cleans air
highly vascular, large surface area
also contains olfactory cells
provides sound resonance when speaking
Pharynx
connects nasal cavity with larynx at the base of skull
has both respiratory and digestive functions
Larynx
connects to trachea
prevents food and liquid from entering lungs
permits air passage

47. Trachea (windpipe)
connects larynx to primary bronchi
Bronchial Tree
gas exchange passages branch apart like branches of a tree
Lungs
hold air for gas exchange
house the bronchi etc.
Alveoli
functional units of respiration
gas exchange takes place here
enormous surface area