Skeletal System Flashcards
Two types of skeleton
Axial - Central bones, protects organs and supports stability.
Appendicular - Limbs, enables movement, provides stability and execution of regular tasks.
How many bones in Axial & list the main bones
80 bones.
Bones that form the skull, laryngeal skeleton, vertebral column, and thoracic cage.
How many bones in Appendicular & list the main bones
126 bones.
Bones that form the arms, hands, feet, and legs (limbs).
Total bones in the human body
206.
Functions of the Skeletal System
Supports movement, balance, and provides structure.
Long bones
Cylinder-like shape, longer than it is wide. Primary function is leverage.
Short bones
Cube-like shape, approximately equal in length, width, and thickness. They provide stability and support while allowing for some motion.
Irregular bones
Complex shape, primary function is to protect internal organs.
Flat bones
Thin and curved, the points of attachment for muscle and also protectors of internal organs.
Sesamoid
Small and round, embedded in tendons. They protect tendons from compressive forces.
Epiphysis
The ends of the long bone.
Diaphysis
The shaft of the long bone.
Articular Cartilage
Padding for the epiphysis.
Periosteum
Membrane that covers the long bone.
Medullary Cavity
The hollow space filled with bone marrow within the long bone.
Red bone marrow
Produces blood cells from the bone.
Yellow bone marrow
Acts as storage for fat.
Compact bone tissue
Wall of the diaphysis.
Spongy bone tissue
Cancellous part of the epiphysis.
Pivot Joint
Uniaxial joint, allows for rotational movement.
Ex). C1-C2 vertebrae articulation
Hinge Joint
Uniaxial joint, allows flexion/extension movements.
Ex). Knee
Condyloid Joint
Biaxial Joint, allows flexion/extension, abduction/adduction, and circumduction movements.
Ex). Knuckles
Saddle Joint
Ditch like bone with allows curving but not rotation. Biaxial Joint, allows flexion/extension, abduction/adduction, and circumduction movements.
Ex). First joint of the thumb
Plane Joint
Multiaxial Joint, allows inversion and eversion of foot or flexion, extension, and lateral flexion of the vertebral column.
Ex). Internal foot joints
Ball-and-socket
Multiaxial joint, allows flexion/extension, abduction/adduction, circumduction, and medial/lateral rotation of movements
Ex). Shoulder and hip joints
Flexion/Extension
Flexion is basically flexing
Extension is folding back in