Flashcards in WEEK 5 Deck (60):
4 types of cells in bone tissue
Osteogenic cell, Osteoblast, Osteocyte, Osteoclast
Function of Osteoblasts
Immature bone building cells
Secrete bone matrix
Function of Osteocytes
Maintain the bone matrix
Repair damaged bone
Function of Osteoclasts
Secrete acids and protein digesting enzymes that break down bone matrix
What percentage of bone mass is compact bone?
What are the 6 main elements of compact bone?
What percentage of body mass is spongy bone?
2 things spongy bone does not have, in comparison to compact bone
What do bones begin as?
What is the strongest type of cartilage?
What are 4 functions of cartilage?
Forms the embryonic skeleton
Covers the ends of bones
Provides support and flexibility in tubes such as trachea, nose and ears
Provides cushioning to joints
What are the 4 major bones shapes?
Irregular (vertebrate, bones in face)
What are the 2 divisions of the skeleton? How many bones?
The bones of the skull can be divided into which 2 categories?
(bones that protect the brain)
(bones that form the face)
What are the 4 cranial bones?
Parietal, Frontal, Temporal, Occipitial
What are the 4 facial bones?
Nasal, Zygomatic, Maxilla, Mandible
What is the Foramen Magnum
Space for spinal cord to enter the skull
How many bones are in the vertebral column? What are they?
What are the 5 regiones of the vertebral column?
Cervical, thoracic, lumbar, sacral, coccygeal
What are the 2 primary curves in the vertebrae?
Thoracic and sacral
What are the 2 secondary curves in the vertebrae?
What are the 5 parts of the vertebra and their functions?
opening that contains the spinal cord
articulation with the ribs in the thoracic region
muscles and ligaments attach to stabalize spine
Superior and inferior articular processes
articulating surfaces between vertebrae
How many vertebrae in the neck?
Articulation with ribs
Large spinous process for muscle attachment
Large vertebral body for bearing weight
Fusion of 5 vertebrae
Protects reproductive, urinary and digestive organs
attaches to axial skeleton to the pelvic girdle
attaches broad muscles that move the thigh
Supports thoracic cavity
Protects organs contained
How many pairs of ribs?
Attaches upper limbs to axial skeleton, consists of 2 pairs of bones (clavicles and scapulae)
Bones in forearm
radius and ulna
How many carpals in wrist?
How many metacarpals in hand?
Upper arm bone
stabilizes forearms movement
Two hip bones can also be called
How are innominate bones joined?
Anteriorly by the pubic symphysis and posteriorly to the sacrum
How many metatarsals in the foot?
Bones in lower leg
tibia and fibula
What are the 7 parts of long bones?
Where diaphysis and epiphysis meet. Contains the epiphyseal plate (cartilage growth plate)
The shaft formed by compact bone. Central space is the medullary cavity
distal and proximal ends of long bones
mostly spongy bone covered by thin layer of compact one
covers surface where bones meet reducing friction
Covers outer surface of bone
Outer fibrous layer
carries blood vessels, lymph vessels and nerves
Inner cellular layer
Contains blood vessel and osteoblasts involved in bone growth and repair
Lines the surface of spongy bone and the central canals of compact bone
contains osteoblasts and osteoclasts
surface for bone growth and remodeling
What 4 situations is bone formed?
Initial formation of bones in the embryo and fetus
Growth of bones in infancy, childhood and adolesence
remodeling of bone (replacement of old bone with new bone throughout life)
repair of fractures
How is bone a dynamic tissue?
osteoclasts are constantly breaking down bone( bone resorption)
Osteoblasts are constantly adding new bone (bone deposition)
4 factors that affect the rate of ossification
process of replacing other tissues with bone
2 types of ossification
Intramembranous and Enchondral
3 steps of intramembranous ossification
Connective tissue sheet is replaced by bone
osteoblasts secrete collagen matrix then calcium salts deposited
Responsible for the development of SOME flat bones (skull plates)
Functions of Fontanels
Allows skull to compress during passage through birth canal
permits rapid growth of the brain in infancy
5 steps of enchondral ossification
Cartilage model of bone is made
Membrane called perichondrium covers the model
Perichondrium is invaded by blood vessels and osteoblasts form within it
Osteoblasts begin producing compact bone matrix and minerals are deposited
Secondary ossification centers from in the epiphysis at about the time of birth
4 steps of bone growth in length
Proliferation zone, cartilage cells undergo mitosis
Hypertrophic zone, older cartilage cells enlarge
Calcification zone, matrix becomes calcified, cartilage cells die, matrix begins deteriorating
ossification zone, new bone formation is occuring
Bone growth in width
Only grows in thickness at the bones surface
Periosteal cells differentiate into osteoblasts and form bony ridges and then a tunnel around periosteal blood vessel
Concentric lamellae fill in the tunnel to form a new osteon