Skeletal System Physiology Flashcards
The structural foundation of any vertebrate. It is the network of different structures that support the overall spatial orientation of the human body.
SKELETAL SYSTEM
It is involved in various processes in the human body because of the multitude of functions that it serves.
SKELETAL SYSTEM
FUNCTION OF THE SKELETAL SYSTEM
SUPPORT
PROTECTION
MOBILITY
STORAGE
MYELOID PRODUCTION
FUNCTION OF THE SKELETAL SYSTEM
- Positional stabilization (orientation)
SUPPORT
FUNCTION OF THE SKELETAL SYSTEM
- Internal organs preservation and safety
PROTECTION
FUNCTION OF THE SKELETAL SYSTEM
- Movement (joints and articulation)
MOBILITY
FUNCTION OF THE SKELETAL SYSTEM
- Mineral deposition (Hydroxyapatite - calcium & phosphates)
STORAGE
FUNCTION OF THE SKELETAL SYSTEM
- Blood cells and stem cells (pluripotential)
MYELOID PRODUCTION
A derivative of mesenchymal cells (middle layer) of the embryo.
SKELETAL SYSTEM
FETAL DEVELOPMENT OF THE SKELETAL SYSTEM
CHONDROBLAST
CHONDROCYTE
OSTEOBLAST
OSTEOCYTE
OSTEOCLASTS
FETAL DEVELOPMENT OF THE SKELETAL SYSTEM
- Progenitor of cartilage (chondrocytes)
CHONDROBLASTS
FETAL DEVELOPMENT OF THE SKELETAL SYSTEM
- Collagen accumulating cell membranes
CHONDROCYTE
FETAL DEVELOPMENT OF THE SKELETAL SYSTEM
- Bone forming derivative of chindrocytes
OSTEOBLAST
FETAL DEVELOPMENT OF THE SKELETAL SYSTEM
- Calcium accumulating cell membranes
OSTEOCYTE
FETAL DEVELOPMENT OF THE SKELETAL SYSTEM
- Calcium degrading osteocytes located in the covering of the bones (periosteum)
OSTEOCLASTS
SKELETAL TISSUES
TENDONS AND TERMINAL SURFACES OF BONES
SOFT CARTILAGE
HARD CARTILAGE
BONE
SKELETAL TISSUES
- Dense CT (hyaline cartilage)
TENDONS AND TERMINAL SURFACES OF BONES
SKELETAL TISSUES
- Loose CT (elastic cartilage)
SOFT CARTILAGE
SKELETAL TISSUES
- Dense CT (fibrocartilage)
HARD CARTILAGE
SKELETAL TISSUES
- Mineralized CT (hydroxyapatite - calcium and phosphates)
BONE
BONE PHYSIOLOGY
RED BONE MARROW
YELLOW BONE MARROW
APPOSITIONAL GROWTH
PERIOSTEUM
BONE PHYSIOLOGY
- Myeloid production (Myeloblast - undifferentiated and immature blood cells)
RED BONE MARROW
BONE PHYSIOLOGY
- Fat storage (Adult - ‘excess nutrient’ and Brown Adipocytes - heat source)
YELLOW BONE MARROW
BONE PHYSIOLOGY
- Conversion of cartilage to bone (bone height increase)
APPOSITIONAL GROWTH
BONE PHYSIOLOGY
- Production of osteoblasts (source of bone regeneration for repair)
PERIOSTEUM
INTRAMEMBRANOUS OSSIFICATION
Development of ossification center: osteoblasts secrete organic extracellular matrix
INTRAMEMBRANOUS OSSIFICATION
CALCIFICATION: calcium and other mineral salts are deposited and extracellular matrix calcifies (hardens)
INTRAMEMBRANOUS OSSIFICATION
Formation of trabeculae: extracellular matrix develops into trabeculae that fuse to form spongy bone
INTRAMEMBRANOUS OSSIFICATION
Development of the periosteum: mesenchyme at the periphery of the bone develops into the periosteum
BONE REPAIR: FRACTURES
HEMATOMA FORMATION
CALLUS FORMATION
CALLUS OSSIFICATION
BONE REMODELING
BONE REPAIR: FRACTURES
- Blood released from damaged blood vessels forms a hematoma
HEMATOMA FORMATION
BONE REPAIR: FRACTURES
- The internal callus forms between the ends of the bones, and the external call forms a collar around the break
CALLUS FORMATION
BONE REPAIR: FRACTURES
- Woven, spongy bone replaces the internal and external calluses
CALLUS OSSIFICATION
BONE REPAIR: FRACTURES
- compact bone replaces woven bone, and part of the internal callus is removed, restoring the medullary cavity
BONE REMODELLING
Bone fracture, if the bone protrudes through the skin
OPEN (or compound) WOUND
Bone fractures, if the skin is not perforated
CLOSED (or simple) WOUND
If the fracture totally separates the two bone fragments it is called
COMPLETE
If the fracture does not separate the two bone fragments it is called
INCOMPLETE
Incomplete fracture that occurs in the convex side of the side of the curve of a bone
GREENSTICK FRACTURE
A fracture is one in which the bone breaks into more than two fragments is called
COMMINUTED (broken into small pieces)
A fracture occurs when one of the fragments of one part of the bone is driven into the spongy bones of another fragment.
IMPACTED FRACTURE
Parallel to the long axis (direction of fracture line)
LINEAR
At right angles to the long axis
TRANSVERSE
At an angle other than a right angle to the long axis
OBLIQUE or SPIRAL
A joint, or an articulation, is a place where two bones come together. Many joints are movable, although some of them allow only limited movement; others allow no apparent movement.
SKELETAL SYSTEM
MAJOR FUNCTIONS OF SKELETAL SYSTEM
- Rigid, strong bone is well suited for bearing weight and is the major supporting tissue of the body.
SUPPORT
Provides firm yet flexible support within certain structure, such as the nose, external ear, thoracic cage, and trachea.
CARTILAGE
Strong bands of fibrous connective tissue that attach to bones and hold them together.
LIGAMENTS
MAJOR FUNCTIONS OF SKELETAL SYSTEM
- Bone is hard and protects the organs it surrounds. For example. the skulk encloses and protects the brain, and the vertebrae surround the spinal cord. The rib cage protects the heart, lungs, and other organs of the thorax.
PROTECTION
MAJOR FUNCTIONS OF SKELETAL SYSTEM
- Skeletal muscles attach to bones by tendons, which are strong bands of connective tissue. Contraction of the skeletal muscles moves the bones, producing body movements. Joints, where two or more bones come together, allow movement between bones. Smooth cartilage covers the ends of bones within some joints, allowing the bones to move freely. Ligaments allow some movement between bones but. prevent excessive movement.
MOVEMENT
Where two or more bones come together, allows movement between bones
JOINTS
MAJOR FUNCTIONS OF SKELETAL SYSTEM
- Some minerals in the blood—principally, calcium and phosphorus—are stored in bone. Should blood levels of these minerals decrease, the minerals are released from bone into the blood. Adipose tissue is also stores
d within bone cavities. If needed, the lipids are released into the blood and used by other tissues as a source of energy.
STORAGE
MAJOR FUNCTIONS OF SKELETAL SYSTEM
- Many bones contain cavities filled with re bone marrow, which produces blood cells and platelets
BLOOD CELL PRODUCTION
EXTRACELLULAR MATRIX
COLLAGEN
PROTEOGLYCANS
EXTRACELLULAR MATRIX
- A tough, rope-like protein
COLLAGEN
EXTRACELLULAR MATRIX
- Large molecules consisting of polysaccharides attached to core proteins, similar to the way needles of a pine tree are attached to the tree’s branches. Can attract and retain large amounts of water between their polysaccharide ‘’needles”
PROTEOGLYCANS
The extracellular matrix of ________ and ________ contains large amounts of collagen fibers, making these structures very tough, like ropes or cables.
TENDONS and LIGAMENTS
The extracellular matrix of ___________ contains collagen and proteoglycans. Collagen makes it tough whereas water filled proteoglycans make it smooth and resilient
CARTILAGE
Most of the mineral in bone is in the form of calcium phosphate crystals called
HYDROXYAPATITE
FOUR CATEGORIES OF BONE
LONG BONE
SHORT BONE
FLAT BONE
IRREGULAR BONE
FOUR CATEGORIES OF BONE
- Longer than they are wide
Ex. Upper and Lower Limbs
LONG BONE
FOUR CATEGORIES OF BONE
- Approximately as wide as they are long.
Ex. Wrist and Ankle
SHORT BONE
FOUR CATEGORIES OF BONE
- Relatively thin, flattened shape.
Ex. certain parts of the Skull, Ribs, Scapulae, and Sternum
FLAT BONE
FOUR CATEGORIES OF BONE
- Have shapes that do not fit readily into the other three categories.
Ex. Vertebrae, Facial bones
IRREGULAR BONE
STRUCTURE OF LONG BONE
- Long bone serves as a useful model for illustrating the parts of a typical bone ends
EPIPHYSIS (growing upon)
FOUR CATEGORIES OF BONE
- A thin layer that covers the ends of the epiphysis where the bone articulates with other bones.
ARTICULAR CARTILAGE
FOUR CATEGORIES OF BONE
- A long bone that is still growing has ________ composed of cartilage, between each epiphysis and diaphysis.
EPIPHYSEAL PLATE (growth plate)
FOUR CATEGORIES OF BONE
- When the bone growth stops, the cartilage of each epiphyseal plate is replaces by bone and becomes ______________
EPIPHYSEAL LINE
Bone contain cavities, such as the large __________________ in the diaphysis, as well as smaller cavities in the epiphysis of long bones and in the interior of other bones.
MEDULLARY CAVITY
Consists of blood forming cells and is the only site of blood formation in adults.
RED MARROW
Most of the outer surface of bone is covered by dense connective tissue, which consists of two layers and contains blood vessels and nerves
PERIOSTEUM
(perio = around)
The surface of medullary cavity is lined with a thinner connective tissue membrane
ENDOSTEUM
(endo = inside)
Each long bone consists of a central shaft and two histology bones.
DIAPHYSIS (growing between)
The periosteum and endosteum contain ____________, which function in the formation of bone, as well as in the repair and remodeling of bone.
OSTEOBLASTS (bone forming cells)
When osteoblasts become surrounded by matrix, they are called
OSTEOCYTES (bone cells)
Present and contribute to bone repair and remodeling by removing existing bone.
OSTEOCLASTS (bone eating cells)
Bone is formed in thin sheets of extracellular matrix called ____________, with osteocytes located between the lamellae within spaces called, ________________
LAMELLAE and LACUNAE
Cell processes extend from the osteocytes across the extracellular matrix of the lamellae within tiny canals called
CANA-LICULI (little canal)
Bone tissue found throughout the skeleton is divided into two major types, based on the histological structure. This is mostly composed of solid matrix and cells.
COMPOUND BONE
Bone tissue found throughout the skeleton is divided into two major types, based on the histological structure. Consists of a lacy network of bone with many small, marrow-filled spaces.
SPONGY BONE
Forms most of the diaphysis of a long bone and the thinner surfaces of all other bones.
COMPACT BONE
Compact bone has a predictable pattern of repeating units. These units are called
OSTEONS
Each osteon consists of concentric rings of lamellae surrounding
CENTRAL CANAL (haversian canal )
Located mainly in the epiphysis of long bones. It forms the interior of all other bones.
SPONGY BONE
Spongy bone consists of delicate interconnecting rods or plates of bone, which resemble the beams or scaffolding of a building.
TRABECULAE
The formation of bone by osteoblasts. After an osteoblast becomes completely surrounded by bone matrix, it becomes a mature bone cell, or osteocyte.
OSSIFICATION
Occurs when osteoblasts begin to produce bone in connective tissue membranes. This occurs primarily in the bones of the skull.
INTRAMEMBRANOUS OSSIFICATION
Osteoblasts line up on the surface of connective tissue fibers and begin depositing bone matrix to form trabeculae. The process begins in areas called _______________, and the trabeculae radiate out from the centers.
OSSIFICATION CENTERS
The bones at the base of the skull and most of the remaining skeletal system develop through the process of ______________ from cartilage models
ENDOCHONDRAL OSSIFICATION
The cartilage models have the general shape of the mature bone. During endochondral ossification, cartilage cells called ____________, increase in number, enlarge and die.
CHONDROCYTES
The center part of the diaphysis, where bone first begins to appear, is called ________________
PRIMARY OSSIFICATION CENTER
A medullary cavity forms in the center of the diaphysis as osteoclasts remove bone and calcified cartilage, which are replaced by bone marrow. Later, ______________ form in the epiphysis
SECONDARY OSSIFICATION CENTERS
Occurs by the deposition of new bone lamellae onto existing bone or other connective tissue.
BONE GROWTH
As osteoblasts deposit new bone matrix on the surface of bones between the periosteum and the existing bone matrix, the bone increases in width, or diameter.
APPOSITIONAL GROWTH
Involves the removal of existing bone by osteoclasts and the deposition of new bone by osteoblasts.
BONE REMODELING
Responsible for changes in bone shape, the adjustment of bone to stress, bone repair, and calcium ion regulation in the body fluids. Also involved in bone growth when newly formed spongy bone in the epiphyseal plate forms compact bone.
REMODELING
Major storage site for calcium in the body, and movement of calcium into and out of bone helps determine blood calcium levels, which is critical for normal muscle and nervous system function.
BONE
