Anatomy & Physiology Unit 3 - The Musculoskeletal System

Skeletal System Functions

• support, protection, movement

• blood cell formation

• storage of inorganic materials

Axial Division

skull, spine, ribs, hyoid bone

Apendicular Division

limbs, scapula, clavicle, pelvic girdle

Humerus

upper arm

Radius

forearm, on thumb side

Ulna

forearm, on pinky side

Tibia

lower leg, thicker bone

Fibula

lower leg, thinner bone

Frontal Bone

forehead area

Temporal Bone

ear area

Occipital Bone

back of head

Parietal Bone

upper sides of head

Sacrum

fused vertebrae below lumbar spine

Coccyx

tailbone

Carpals

wrist bones

Metacarpals

finger bones in palm area

Carpal Phalanges

extended fingers

Proximal Phalanges

knuckle to 1st finger joint

Middle Phalanges

1st finger joint to 2nd one (NOT on thumb)

Distal Phalanges

fingertips

Tarsals

ankle bones

Metatarsals

toe bones in sole area

Tarsal Phalanges

extended toe bones

Epiphyses

ends of bones

Epiphyseal Line

growth plate; found on both ends of long bone

Diaphysis

shaft of bone

Hyaline Cartilage

cartilage at ends of bone

Periosteum

membrane that covers the whole bone

Medullar Cavity

chamber filled w/ bone marrow

Spongy (Cancellous) Bone

soft, airy bone near epiphyses

Compact Bone

hard, packed bone along shaft

Endosteum

lining of Medullar Cavity

Red Marrow

• produces blood cells

• found in flat bones

Yellow Marrow

• fat storage

• found in long bones

Osteoblasts

bone-forming cells

Osteoclasts

bone-reabsorbing cells

Hematopoiesis

process of blood cell production

Collagen

structural protein in bone

Joint Capsule

• surrounds joint

• made of connective tissue

Synovial Membrane

produces synovial fluid

Synovial Fluid

• joint cavity containing fluid

• provides nutrients to hyaline cartilage

Ball & Socket Joints

• shoulder, hip

• flexion/extension, adduction/abduction, rotation

Hinge Joints

• elbow, knee

• flexion + extension

Pivot Joints

• radius/ulna, neck/head joint

• rotation, pronation/supination of arm

Fibrous Joints

• completely immovable (fused by CT)

• cranium

Cartilaginous Joints

• semi-mobile (joined by cartilage)

• spine

Synovial Joints

• fully movable (connected via synovial cavity)

• knee, elbow, wrist

Knee Joint Bones

femur, tibia, fibula, patella

Joint Accessory Structures

cartilage, ligament, tendon

Arthritis

• occurs when hyaline cartilage degrades and bones make contact w/ one another

• surgical treatments include total joint replacement (mechanical joint)

Osteoperosis

• bone density/mass decreases, making it weak and brittle

• new bone creation slower than old bone removal

• heightened risk of fractures

Skeletal Muscle Tissue

• found in muscles attached to bones

• voluntary movement to move body

• multinuclear, each cell spans full length of muscle

Smooth Muscle Tissue

• found in organs (digestive tract)

• involuntary movement to move organs to digest

• mononuclear

Cardiac Muscle Tissue

• found in heart

• involuntary movement to beat heart

• mononuclear

Agonist Muscle

the contracting muscle in a movement

Antagonist Muscle

the relaxing/lengthening muscle in a movement

Myofibril

many tubes that make up a single muscle fiber that contain Actin + Myosin bands

Sarcoplasm

the space b/w myofibrils in a muscle fiber

Sarcolemma

membrane surrounding bundle of myofibrils

Muscle Fiber/Cell

bundle of myofibrils

Endomysium

membrane surrounding a single muscle fiber on top of sarcolemma

Fascicle

bundle of muscle fibers

Perimysium

membrane surrounding a fascicle

Endomysium

membrane surrounding the whole muscle

Sarcomere

sarcolemma-surrounded tube of actin + myosin bands (basically a single muscle fiber)

Insertion

attachment pt of muscle to the moving bone

Origin

attachment pt of muscle to nonmoving bone

Pectoralis Major

• anterior chest

• flexion, adduction, arm rotation at shoulder

Rectus Abdominis

• interior abdomen

• flexes spine

External Oblique

• deep to rectus abdominis

• laterally flexes/rotates spine

Internal Oblique

• deep to external oblique

• laterally flexes/rotates spine

Trapezius

• upper back

• elevate/depress/adduct scapula

Deltoid

• superior shoulder

• abduct/extend/rotate shoulder

Biceps Brachii

• anterior arm

• flexes elbow, supinates forearm

Triceps Brachii

• posterior arm

• extends elbow + shoulder

Gluteus Maximus

• posterior buttocks

• extend/rotate/abduct hip

Psoas

• medial anterior femur

• flex hip + trunk

Rectus Femoris (quadriceps)

• medial posterior femur

• extend knee, flex hip

Biceps Femoris (hamstrings)

• hamstring

• flex knee, extend hip

Gastrocnemius

• calf

• plantar flexes ankle