Module 4 : Skeletal System Flashcards
Functions of the Skeletal System
-Supportive framework of the body
- protection of internal organs
- moveable joints promote movement
- maintains homeostasis of blood calcium (calcitonin [CT] and Parathyroid hormone [PTH]
- Hemopoiesis (blood cell formation in red bone marrow)
Gross structure of bones;
four major bone types
long bones
short bones
flat bones
irregular bones
also sesamoid (round) bones
Structure of long bones
- diaphysis
- medullary cavity
- epiphyses
- articular cartilage
- periosteum
- endosteum
Microscopic structure of bones; bone tissue structure
cancellous bone (spongy bone)
- trabeculae
compact bone
- osteon, concentric lamella
- osteocytes, lacunae, canaliculi
Microscopic structure of bones; cartilage tissue structure
cartilage
- chondrocytes
Bone Development
making and remodeling bone
- ongoing process of the formation of new bone by osteoblasts and the reabsorption of bone by osteoclasts
endochondral ossification
- cartilage models are gradually replaced by calcified bone
Intramembranous ossification
- bones that are formed by the calcification of fibrous membranes
Human skeleton; Axial skeleton
consists of 80 bones that include the skull (cranial bones, ear bones, face bones), spine (vertebrae), thorax (ribs, sternum), and hyoid bone
Human skeleton; appendicular skeleton
consists of 126 bones that include the upper extremities (shoulder/pectoral girdle) and the lower extremities (hip/pelvic girdle)
Axial skeleton
Skull
- cranial bones
- ear bones
- face bones
spine
- vertebrae
thorax
- ribs
- sternum
hyoid bone
appendicular Skeleton
upper extremities
- pectoral (shoulder) girdle
- arm and forearm bones
- wrist bones
- hand bones
lower extremities
- pelvic (hip) girdle
- thigh and leg bones
- ankle bones
- foot bones
Skeletal Variations
size
shape of pelvis
size of pelvic inlet
pubic angle
age differences
environmental factors
Joints; articulation of bones
-joints hold bones together and make it possible for movement to occur
- every bone except the hyoid connects to at least one other bone
Joints; types of joints
Synarthroses (no movement)
- fibrous connective tissue grows between articulating bones (sutures of skull)
Amphiarthroses (slight movement)
- cartilage connects articulating bones (symphysis pubis)
Diarthroses (free movement)
- most joints belong to this type
Diarthroses
structures of freely movable joints
- joint capsule and ligaments hold adjoining bones together but permit movement at joint; structure determines type of movement (ball and socket, hinge, pivot, saddle, gliding, and condyloid)
- articular cartilage
- synovial membrane
- joint cavity
- bursa
Types of joint movements
flexion
extension
abduction
adduction
rotation
circumduction
Glossary: abduct
To move away from the midline of the body (or region)
Glossary: Abduction
moving away from the midline of the body; opposite motion of adduction
Glossary: Acetabulum
socket in the hip bone (pelvic bone) into which the head of the femur fits
Glossary: Adduction
moving toward the midline of the body or region; opposite of abduction
Glossary: Adduct
to move toward the midline of the body or region
Glossary: Amphiarthrosis (pl. amphiarthroses)
Slightly movable joint such as the joint joining the two pubic bones
Glossary: Appendicular skeleton
the bones of the upper and lower extremities of the body
Glossary: Arch
any structure resembling an arch or arc, as in archlike arrangement of foot support structures; the process of forming an arch, as when flexing or extending the spine to form an arch
Glossary: Articular cartilage
Cartilage covering the joint ends of bones
Glossary: Athletic trainer
health-care professional who works with a physician and specializes in prevention, diagnosis, and therapy of sports-related injuries
Glossary: articulation
Joint
Glossary: axial skeleton
the bones of the head, neck, and torso
Glossary: Atlas
another name for the first cervical vertebra (C1)
Glossary: Axis (pl. Axes)
central line or structure around which something turns; the second cervical vertebra
Glossary: Ball-and-socket joint
type of synovial joint in which the spherical end of one bone fits into a cuplike socket of another bone or structure
Glossary: Bursa (pl. Bursae)
Small, cushionlike sac found alongside joints, cushioning moving bones
Glossary: Calcitonin (CT)
A hormone secreted by the thyroid that decreases calcium in the blood
Glossary: Calcaneous
heel bone; largest tarsal bone in the foot
Glossary: Cancellous bone
Porous bone tissue found inside bone organs; also called spongy bone or trabecular bone
Glossary: Canaliculus (pl. canaliculi)
An extremely narrow tubular passage or channel in compact bone
Glossary: Carpal
relating to the wrist
Glossary: Cartilage
a type of fibrous connective tissue that has the consistency of a firm plastic or gristlelike gel
Glossary: Central canal
any tubelike passage at the center of a structure, such as the canal running through the center of the spinal cord or through the center of each osteon in compact bone
Glossary: chest
thorax
Glossary: Chiropractor
physician specializing in therapy based on the principle that alignment of the skeleton promotes healing
Glossary: Chondrocyte
Cartilage cell
Glossary: Circumduct
move the distal end in a circular path
Glossary: Circumduction
the process of moving the distal end of a body part in a circular path
Glossary: Clavicle
collarbone; connects the upper extremity to the axial skeleton
Glossary: Coccyx
last bone of the vertebral column, made up of four or five vertebrae that have fused together
Glossary: concave curvature
inward or secondary curvatures of the adult vertebral column in the cervical and lumbar regions
Glossary: Compact bone
dense bone
Glossary: concentric lamella (pl. lamellae)
Ring of calcified matrix surrounding the haversian canal
Glossary: condyloid joint
ellipsoidal joint in which an oval process fits into an oval socket
Glossary: Convex curvature
the thoracic or sacral outward curving of the adult vertebral column; an infant has single primary outward curvature the length of its spine
Glossary: Coxal bone
the pelvic bone or hipbone (also known as the os coxae or the innominate bone) formed by fusion of three distinct bones (ilium, ischium, and pubis) during skeletal development
Glossary: cranium
bony vault made up of eight bones that encase the brain
Glossary: Cruciate ligament
either of two crossed ligaments inside the knee joint cavity that connect the tibia to the femur; the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL)
Glossary: Diaphysis (pl. diaphyses)
shaft of a long bone
Glossary: Diarthrosis (pl. diarthroses)
freely movable joint