Chapter 7&8: The Skeletal System - Bone Tissue Flashcards
Bone tissue and the skeletal system perform which functoins?
- Support
- Protection
- Assistance in movement
- blood cell production
- mineral homeostasis
- triglyceride storage
What does red bone marrow consist of anf where is it located?
made of: developing blood cells, adipocytes, fibroblasts, and macrophages.
Found in: developing bones of fetus and in some adult bones ( skull, vertebrae, stermun, ribs, pelvis, and ends of arm and thigh bones.
What does yellow bone marrow consist of and when can you find it?
Made mostly of adipocytes which store triglyceride and some blood cells.
most red bone marrow turns into yellow bone marrow with age.
What are the 4 different types of bones?
- short
- long
- flat
- irregular
What makes a bone a long bone?
Which bones are long bones?
Greater length than width and consist of a shaft and a variable number of ends.
Long bones include:
femur (thigh), tibia, and fibula
humerus (arm), ulna, and radius
phalanges (fingers and toes)
What makes a bone a short bone?
Which bones are short bones?
Somewhat cube-shaped and nearly equal in length and width.
Wrist and ankle bones
What makes a bone an irregular bone and which bones are they?
Have complex shapes and cannot be group into other groups.
include vertebrae and some facial bones.
A typical long bones consists of what 7 parts?
- diaphysis
- epiphyses
- metaphyses
- articular cartilage
- periosteum
- medullary cavity
- endosteum
What 3 components make up the extracellular matrix of a bone?
25% water
25% collagen foberes
50% crystallized mineral salts
______ is initiated by osteoblasts.
Calcification
What are osteogenic cells?
Unspecialized stem cells derived from mesenchyme.
As osteoblasts surround themselves wit hextracellular matrix, they become traped in their secretions and become _____.
Osteocytes
What bone cells undergo cell devision?
Osteogenic cells
?What does compact bone tissue consist of?
Osteons with little spaces between them.
What is spongy bone tissue composed of?
Trabeculae surrounding many red bone marrow-filled spaces.
Where can you find spongy bone tissue?
Forms most of the short, flat and irregular bones, and epiphyses of long bones.
What is the function of spongy bone tissue?
stores red bone marrow and provides some support.
Bone forms by a process called ______.
Ossification
Bone formation in an embryo of fetus occurs by what type of ossification?
Intramembranous and endochondrail ossification,
which involves the replacement of pre-existing CT with bone.
What type of ossification occurs within mesenchyme arranged in sheetlike layers that resemble membranes?
Intramembranous Ossification
What type of ossification occurs within a cartilage model derived from mesenchyme?
Endochondral Ossification
The primary ossification center of a long bone is in the ______.
diaphysis
What is a fracture?
Any break in a bone
What is a partial fracture?
An incomplete break across the bone,
such as a crack.
What is a complete fracture?
A complete break across the bone,
bone is broken into 2 or more pieces.
What is a closed fracture?
the fractured bone does not break through skin.
*also called SIMPLE
What is invloved in fracture repair?
- Phagocytes begin to remove any dead bone tissue
- Chondroblasts form firbocartilage at fracture site taht bridged the broken ends of bone.
- Fibrocartilage is converted to spongy bone tissue by osteoblasts.
- Bone remodeling occurs.
What is a open fracture?
The broken ends of bone protrude through skin.
*also called COMPOUND
Bone store and release calcuum and phosphate, controlled maily by ________.
Parathyroid hormone (PTH)
Which 2 minerals do bone tissues store the most of?
Calcium and Phosphorus
What makes a bone a flat bone and which bones are they?
Generally thin, afford considerable protection, and provide extensive serface for muscle attachment.
Crainal bones, sternum, ribs, and scapulae.
What are the 4 major types of cells present in bone tissue?
- Osteocytes
- Osteogenic cells
- Osteoblasts
- Osteoclasts
What are osteoblasts and what is their function?
Bone-building cells
they synthesize and secrete collagen fibers and other organic components needed to build the extracellular matrix of bone tissue.
What do osteoclasts release?
Release powerful lysosomal enzymes and acids that digest the protein and mineral components of the bones extracellular matrix.
Where are osteogenic cells found?
Found along the inner portion of periosteum,
in the endosteum, and
in canals within bone that contain blood vessels.
What is the function of compact bone tissue?
Protection, suppost, and resists stress.
What is bone remodeling?
Old bone is constantly destroyed by osteoclasts,
while new bone is constructed by oseoblasts.
How does mechanical stress increase bone strength?
increases the deposition of mineral salts and
production of collagen fibers
What happens when mechanical stress is removed?
Weakens bones through demineralization and collagen fiber reduction.
Which cells have a ruffled boarder and secrete hydrochloric acid?
Osteoclasts
The spurt of growth in puberty results from cell proliferation and hypertrophy in what part of the bone?
epiphyseal plate
Osteoclasts are most closely related, by common decent, to what cell?
Blood cells
The walls between cartilage lacunae break down in what zone?
Bone deposition
A child jumps to the ground from the top of the playground. What causes his leg bones not to shatter?
Contains collagen fibers
Where does one long bone meet another?
Epiphysis
What is calcitroil made of?
7-dehydrocholesterol
What is a sign of osteoporosis?
a wrist fracture
Calcium phosphate crystallizes in bone as a mineral called ______.
Hydroxyapatite
Osteocytes conact each other through channels called ______ in the bone matrix.
Caniculi
A calcium deficiency called ___________ can cause death by suffocation.
Hypocalcemia
The most active form of vitamin D, produced mainly by the kidneys, is _______.
Calcitriol
The most common bone disease is _______.
Osteoporosis
A pregnant, poorly nourished woman may suffer a softening of the bones called _______.
Osteomalacia
What does the tubercle of a rib articulate with?
the transverse process of a vertabra.
The disc-shaped head of the radius articulates with the _______ of the humerus.
Capitulum
What body supports your body weight when you are sitting down?
the ischium
Gaps between the cranial bones of a infant are called ______.
fontanels
The external auditory canal is a passage in the ______ bone.
temporal
Bones of the skull are joined along what lines?
sutures
The _____ bone has great ans lesser winngs and protects the pituitary gland.
Sphenoid
A herniated disc occurs when a ring called the ______ cracks.
Anulus
The transverse ligament of the atlas holds the _____ of the axis in place.
dens
