Skeletal and Muscular System

Long Bones

longer than they are wide, two ends contain spongey bone, primarily compact bone, stress absorption (e.g. phalanges, femur, humerus)

Short bones

roughly cube shaped, mostly spongey bone (e.g. carpals, tarsal)

irregular bones

complicated shapes for specific duties
protects vital organs (e.g. vertebrae)

Flat bones

thin, large surface for muscle attachment (e.g. sternum)

sesamoid bones

embedded in tendons, small and round, protects from wear and tear (e.g. patella)

skeletal system functions

1. support (for tendons and ligaments, framework of body)

2. protection (vital organs like heart, brain)

3. movement (bones work together to move)

4. storage

5. blood cell production

Types of Muscles

skeletal muscle, smooth muscle, cardiac muscle

Skeletal muscles

voluntary muscles that cause body movement (bicep)

Smooth muscles are

involuntary muscles, line blood vessels and walls of digestive system (digestive system)

Cardiac muscles are

involuntary, make up walls of the heart (heart)

Muscular system function

movement, posture, heat production

fast twitch fibers

White muscle fibers that contract rapidly and forcefully but fatigue quickly

slow twitch fibers

Red muscle fibers that contract at a slow rate and have very good endurance

Types of contractions

isotonic, isometric, isokinetic

isotonic contraction

muscle shortens because muscle tension exceeds load (e.g. push-up)

isometric contraction

Muscle contracts but there is no movement, muscle stays the same length (e.g. holding tennis raquet)

isokinetic contraction

a muscle fiber contraction in which the velocity of the contraction is kept constant (use of specialised gym equipment

cranium

mandible

Clavicle

Scapula

Sternum

Humerus

ribcage

Vertebrae

pelvis

radius

ulna

Carpals

metacarpals

Phalanges

femur

Patella

tibia

fibula

Tarsals

Metatarsals

Deltoid

biceps brachii

rectus abdominis

quadriceps

tibialis anterior

pec major

Sartorius

Trapezius

latissimus dorsi

triceps brachii

obliques

Gastrocnemius

gluteus maximus

hamstring

vertebrael column

cervical, thoracic, lumbar, sacrum, coccyx (Cool Things Like Steph Curry)

cervical vertebrae

7

thoracic vertebrae

12

lumbar vertebrae

5

Sacrum Vertebrae

5

Coccyx Vertebrae

4

appendicular and axial skeleton

Agonist muscle

The muscle primarily responsible for movement of a bone. Shortens in length (Triceps Brachii)

antagonist muscle

The muscle opposite the agonist, which must relax and lengthen during contraction of the agonist.

Example of Agonist and Antagonist muscle

Bicep Curl

Longest bone in the body

femur

Longest muscle in the body

Sartorius

skeletal joints

-Ball and Socket

-Hinge

-Pivot

-Saddle

-Condyloid

-Gliding

Ball and socket joint

One bone has rounded end, fits into another bone (shoulder, hip)

Hinge joint

Only one plane of movement (elbow, knee)

Pivot joint

Allow bone to spin and twist around other bone (cervical vertebrae)

Saddle joint

Allow back, forth and side to side motion, but limited rotation (thumb)

Condyloid joint

Has two axis, allow sideways, back and forth movement (Wrist)

gliding joint

Allow bones to glide past each other (carpals, tarsals)