- "Compact, dense bone that is found in the shafts of long bones and the vertebral endplates."
- Also called Compact bone.
- Makes up 75% of the human skeleton.
- Spongy bone compased of thin plates that form a honeycome pattern; predominantely found in the ends of long bones and the vertebral bodies.
- Also called Cancellous bone
- Provides a large surface area for mineral exchange and helps to maintain skeletal strength and integrity.
- Makes up 25% of the human skeleton.
The shaft of a long bone
The end of a long bone.
- The hollow space inside the diaphysis of a long bone.
- Used as a storage site for fat
- Also called the Yellow Bonen Marrow Cavity
- Lined by the endosteum
A soft connective tissue lining the internal surface of the diaphysis (medullary cavity) on a long bone.
- Also called a Growth Plate
- Separates the diaphysis and the epiphysis in children and young adults
- Location of bone growth.
- "After growth phases are complete, it is replaced by bone and called the Epiphyseal Line."
- "A double-layered connective tissue sheath surrounding the outer surface bones, except for the articular cartilage."
- Contains nerves and blood vessels and serves to cover and nourish the bone.
- Serves as the attachement sites for tendons/muscles.
Cells that build up the bones.
Cells that dissolve the bone.
- Form follows function
- Changes in bone structure coincide with changes in bone function.
- Bone is capable of increasing its strength in response to stress/force (e.g. exercise) by creating more bone.
What percent of the adult skeleton is remodeled each years?
"Approximately 10%, which mean the entire skeleton is remodeled in approximately 10 years."
How many bones in the Human Skeleton?
- 206 total
- 74 in the Axial Skeleton
- 126 in the Appendicular Skeleton
- 6 Auditory ossicles
- 74 Bones
- Vertebral Column (including the Sacrum and Coccyx)
Main Functions of Axial Skeleton
- Provide the main axial support for the body
- Protect the Central Nervous System (CNS)
- Protect the organs of the thorax
Bones of the Vertebral Column
- Total 24 (or 33)
- 7 Cervical
- 12 Thoracic
- 5 Lumbar
- (5 Sacral - Fused)
- (4 in Coccyx - Fused)
Three Main types of Joints
- "Held tightly together by fibrous connective tissues, allowing little or no movement."
- "Synarthroidal: ""Immovable Joint"""
- "Examples: Cranial Sutures, distal Tibiofibular joint"
- Bone are connected by cartilage and allow little or no movement.
- "Amphiarthroidal (""Slightly Moveable Joint"")"
- "Includes Symphyses, which contain a fibrocartilaginous pad or disk, as in pubic symphysis or vertebral discs."
- Diarthoidal (Freely moveable)
- Articular (Hyaline) cartilage
- Articular Capsule
- Synovial Membrane
- Synovial Fluid
Uniplanar (uniaxial) joints
- Joints that move in only one plane and have only one axis of rotation.
- "Also called ""hinge joints"""
Biplanar (biaxial) joints
- Allow movement in two planes that are perpendicular to each other.
- "e.g. Knee, Hand, Wrist"
Multiplanar (triaxial) joints
- Allow movement in three planes.
- "e.g. hip, thumb, shoulder"
Four general types of movements of synovial joints?
"A group of nerve cells bodies, usually located in the PNS."
Major Paired Nerves
- 12 Cranial
- 8 Cervical
- 12 Thoracic
- 5 Lumbar
- 5 Sacral
- 1 Coccygeal
Divisions of the Autonomic Nervous System
- Sympathetic Nervous System
- Parasympathetic Nervous System
Divisions of the Efferent Nerves
- Autonomic Nervous System
The site at which a motor neuron transmits information to a muscle fiber.
- Specialized bulblike mechanoreceptors located in the subcutaneous tissues of the skin (and in joint capsules) that are responsible for detecting pressue.
- "Occur abundantly in the skin of palms, soles, and in joints."
- A Specialized mechanoreceptor located in the superficial aspect of the skin responsible for detecting light touch.
- "Occur abundantly in the skin of the fingertips, palms, soles, lips, tongue, and face."
- A specialized mechanoreceptor located in the joint capsule responsible for detecting joint compression.
- Any weightbearing activity stimulates these receptors.
Golgi Tndon Organ (GTO)
- A musculotendinous sensory organ (proprioceptor) within tendons that detects tension within its associated muscle when the muscle is contracted or stretched.
- Causes autogenic inhibition (relaxation) in its assocated muscle and activation in the antagonist muscle.
- Connected to approximately 15-20 muscle fibers.
- A musculotendinous receptor located in the muscle belly which lies parallel to the muscle fibers.
- Senses when a muscles is stretched and caused the muscle to then reflexively contract (reflex stretch)
- Also causes the antagonist muscle to relax (reciprocal inhibition).
- Three semicircular canals in the inner ear that lie at right angles to each other
- "Part of the CNS that coordinates reflexes of the eyes, neck, and body to maintain equilibrium in accordance with posture and movement of the head."