Inferior
Below or further away from the head
Superior
Above or nearer to the head
Proximal
Nearer to where a limb attaches to the body
Distal
Further away from where a limb attaches to the body
Posterior
Behind or nearer to the back
Anterior
The front or nearer to the front
Internal
Located inside or further away from the surface
External
Located on or near the surface
Lateral
Further away from the midline of the body
Medial
Closer to the midline of the body
Axial Skeleton
The skull, ribs/thoracic cage, sternum, vertebral column
Skull
Protects the brain, forms the orbit of the eyes, attachment to muscles, and structure to the face
Ribs/Thoracic Cage
Protects and supports internal organs, such as the heart and lungs
Sternum
A flat bone that starts at the bottom of the throat and runs to about halfway down the center of the chest
Vertebral Column
Supports the spinal cord and head, provides articulation sites for ribs and innominate bones of the pelvic girdle
Cervical Vertebrae
Smallest vertebrae, more movement than thoracic and lumbar vertebrae
Thoracic Vertebrae
Restricts movement, ribs are attached to the side of each vertebrae
Lumbar Vertebrae
The biggest and strongest of the vertebrae, plays a major role in weight-bearing
Sacral Vertebrae
Transmits weight from body to pelvis and legs
Coccygeal Vertebrae
Tailbone
Pectoral (Shoulder) Girdle
Anchors and supports the upper limbs, attachment site for muscles that move the arms
Pelvic (Hip) Girdle
Supports and protects abdominal organs, transfers weight from upper body to lower limbs
Upper Extremity/Arms
Humerus, ulna, radius, carpal bones, metacarpals, and phalanges
Lower Extremity/Legs
Femur, tibia, fibula, tarsal bones, metatarsals, and phalanges
Long Bones
Long cylindrical shaft, enlarged at both ends, important for movement (e.g., femur, metatarsals, clavicle)
Short Bones
Small and cube-shaped, articulate with more than one other bone (e.g., carpals, tarsals)
Flat Bones
Curved surfaces, provide protection and muscle attachment (e.g., sternum, scapula, ribs, pelvis)
Irregular Bones
Specialized shapes and functions (e.g., vertebrae, sacrum, coccyx)
Epiphysis
Two end partitions of a long bone, covered by articular cartilage
Diaphysis
Compact part of a long bone, long shaft covered by periosteum membrane
Periosteum
Membrane of a long bone for protection
Spongy Bone
Lighter and less dense than compact bone, contains red bone marrow
Articular Cartilage
Smooth tissue that covers the ends of bones, reduces friction and absorbs shock
Bone Marrow
Soft fatty substance in bone cavities, produces blood cells (red marrow) and stores fat (yellow marrow)
Compact Bone
External layer of bone, dense and filled with passageways for nerves, blood vessels, and lymphatic system
Marrow Cavity
Space within the diaphysis where yellow marrow is stored
Connective Tissue
Joins bodily structures, reinforces joints, transports nutrients, made up of proteins and intercellular fluid
Fixed Joints
Very stable, no observable movement, joined by strong fibers called sutures
Cartilaginous Joints
Allows slight movement, ends covered with fibrocartilage pads
Synovial Joints
Most common type, allows a wide range of movement, characterized by joint capsule and synovial membrane
Ligament
Band of strong fibrous connective material, joins bone to bone and provides stability
Pads of Fat
Found between capsule, bone, or muscle, increases joint stability and reduces friction
Meniscus Trough
Flexible discs of fibrocartilage, improves fit between bone ends and reduces wear and tear
Bursae Fluid
Filled sac found between tendon and bone, reduces friction in high-stress areas
Articular Cartilage
Smooth and spongy covers of the
Gliding
Usually flat or slightly curved, slide across each other, with the least amount of movement
Hinge
The articular surfaces have been fused so movement in one direction, joined by ligaments, movement is only allowed in one plane (extension/flexion)
Pivot
The rounded surface of one bone that rolls around a ring formed by bone and ligament
Condyloid
A ball-shaped bone that fits into a cup
Saddle
bone that fits into a bone shaped like the legs, and can move up, down, side to side
Ball and Socket
A sphere-shaped bone that fits into a rounded cavity, covered in cartilage to prevent friction and a high range of movements
Contractility of Muscles
The ability of the muscle to contract and generate a force when it is stimulated by a nerve
Extensibility of Muscles
The ability to extend before its normal resting state
Elasticity of Muscles
The muscle's ability to return to its original resting length
Atrophy of Muscles
Muscle wastage, caused by lack of physical activity, poor nutrition, and disease
Hypertrophy of Muscles
Growth and increase in the size of the muscle, most commonly as a result of weight training
Nerve Stimuli of Muscles
A nerve that sends a signal for the muscle to contract
Oxygen to Muscles by Capillaries
Gaseous exchange that occurs in the capillaries so oxygen can be delivered to the muscles
Skeletal Muscles
voluntary muscles that connect to bones and allows a wide range of movements and functions
Cardiac Muscles
involuntary striated muscle tissue found only in the heart and is responsible for the ability of the heart to pump blood
Smooth Muscles
type of muscle that contracts without any voluntary control and are located in walls of hollow visceral organs (expect the heart)
Cerebral Arteries
Arteries that supply blood to the cerebellum and cerebrum
Communicating Arteries
Arteries that surround the pituitary gland and form the Circle of Willis, allowing blood supply from carotid or vertebral arteries.
Carotid Artery
Internal and external branches that supply blood to the cerebrum and face, scalp, skull base, and neck, respectively.
Vertebral Artery
Artery that originates from the subclavian artery and supplies blood to the brain.
Blood-Brain Barrier
Protective barrier that separates circulating blood from the brain's extracellular fluids.
Glucose
Simple carbohydrate that provides fuel for the brain.
Oxygen
Essential for brain function, growth, and healing.
ATP (Adenosine Triphosphate)
Vital nucleotide for brain function, enhancing nutrient delivery and waste removal.
Effect of Low Glucose or Oxygen Levels
Mental confusion, dizziness, convulsions, loss of consciousness due to insufficient glucose or oxygen supply to the brain.
Synovial Fluid
Slippery fluid that fills the joint capsule