Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
67 Cards in this Set
- Front
- Back
Bone are make up of several different types of tissue working together: (7) |
Bone Tissue Cartilage Dense Connective Tissue - Ligaments Epithelium Various blood forming tissues Adipose tissue Nervous tissue |
|
Each individual bone in a ____ because ___ |
organ, made up of several tissues |
|
Bones along with cartilage make up ____ system |
skeletal |
|
The skeletal system performs five basic functions: |
1. Support 2. Storage of Minerals & Lipids 3. Blood Cell Production 4. Protection 5. Leverage |
|
Skeletal system stores: |
Minerals and Lipids. Bones store and release several minerals, especially calcium and phospate. The yellow marrow of adult dones is a site of triglyceride storage |
|
The ___ marrow of adult dones is a site of _____ storage |
yellow, triglyceride |
|
Hemopoiesis |
Blood cell production - red & white blood cells and other blood elements are produced in the red marrow of bones |
|
The skeletal system protects.... |
many organs by bony coverings (e.g. skull -> brain) |
|
Leverage of skeletal system |
bones assist skeletal muscles to produce movement |
|
Structure of a long bone (7) |
1. Diaphysis 2. Epiphysis 3. Metaphysis 4. Medullary Cavity 5. Periosteum 6. Endosteum 7. Articular Cartilage |
|
Diaphysis |
the tubular shaft of the bone, includes a layer of solid, compact bone |
|
Epiphysis |
the expanded areas at ends of the bone (consists mostly of spongy bone) |
|
Metaphysis |
the areas between the epiphysis and diaphysis. Areas where a long bone can grow in length. |
|
Medullary Cavity |
the space within the diaphysis that contains the yellow marrow in adult long bones |
|
Periosteum |
connective tissue covering the surface of the bone. Contains osteoprogenitor cells that allow bones to grow in diameter or thickness, not in length. |
|
Endosteum |
lining of marrow cavity, contains some osteoprogenitor cells and connective tissue |
|
Articular Cartilage |
at the ends of long bone, reduces friction and absorbs shock at the joints |
|
Flat Bone |
resembles a spongy bone sandwich with layer of compact bone covering a core of spongy bone. (e.g.. parietal bone, pelvic bone) |
|
Bone Matrix |
Very dense and is composed of 33% collagen fibers and 67% inorganic components (mostly calcium salts) |
|
Osteogensis |
The process of creating bones |
|
Different types of bone cells (4) |
Osteoprogenitor Osteoblast Osteocyte Osteoclast |
|
Osteoprogenitor |
unspecialized stem cells of bone tissue. Stem cell divides to form another stem cell and a daughter cells that differentiates. |
|
Osteoblast |
Cells that responsible for calcification |
|
Osteocyte |
mature bone cells (the most abundant bone cells). As osteoblasts surround themselves completely with matrix they turn into osteocytes. Osteocytes no longer secrete matrix. They maintain bone metabolism (i.e. exchange of nutrients and wastes with blood In event of bone damage osteocytes can convert back to osteoblasts or osteoprogenitor cells to participate in repair |
|
Osteoclasts |
giant cells that remove and recycle bone matrix - can release acids and enzymes that digest bone matrix as part of normal growth, repair or for mineral homeostasis -they are not related to the first 3 cell types, they are a type of macrophage |
|
Homeostasis of Bone |
Osteoclasts are constantly removing matrix, and osteoblasts are always adding it. Balance between is essential. If the osteoclasts remove calcium salts too fast, the bone can weaken. |
|
Two types of bone |
Compact, Spongy |
|
Osteons |
How compact bone is arranged with very little space between them. Each contain osteocytes arranged in concentric layers around a central canal that contains blood vessels. All are aligned in the same direction, along lines of stress. Thus the shaft does not bend, even when extreme force is applied to either end. |
|
Spongy Bone |
Has no osteon. Consists of trabeculae surrounding many red marrow filled spaces. Found where bones are not heavily stressed, mostly in short, flat, irregular shaped bones and in the epiphyses of long bones. Spongy bone tissue is light and support/protects the red bone marrow |
|
Two ways bones of the body are formed |
Endochondral & Intra membrane ossification |
|
Intra Membrane Ossification |
Happens between membranes, forms skull |
|
6 steps of Endochondral Ossification |
Step 1 chondrocytes in the center of hyaline cartilage enlarge & form struts which begin to calcify. Then the enlarged chondrocytes die, leaving cavities in the cartilage Step 2 Blood vessels grow around the edges of cartilage; cells in the perichondrium change to osteoblasts, producing a layer of superficial bone around the shaft which will continue to grow & become compact bone (appositional growth) Step 3 Blood vessels enter the cartilage, bringing osteoblasts, spongy bone develops at the primary ossification center Step 4 Remodeling creates a marrow cavity, bone replaces cartilage at the metaphyses Step 5 Capillaries & osteoblasts enter the epiphyses, creating secondary ossification centers Step 6 Epiphyses fill with spongy bone, cartilage remaining within the joint cavity is the articulation cartilage (Hyaline cartilage only in this phase) |
|
Canaliculi |
Arms reaching out to other cells from osteocytes |
|
Where do Osteocytes live? |
Lacunae |
|
Functions of Osteocytes |
Maintain matrix - protein and mineral content Help repair damaged bone |
|
Ways that calcium concentration is balanced in blood stream. |
Calcium & Phosphate absorbed from diet by intestines Kidneys remove calcium Osteoblast use up calcium, Osteoclasts release calcium |
|
Three main phases of bone growth and remodelling in humans: |
1.Birth to Adolescence - more bone is produced than is lost due to resorption 2.Young Adults - the rates of boneproduction and reabsorption are about the same (appx. 20% is recycled and replaced each year) 3.Middle-age to elderly - bone mass decreases because more bone is reabsorbed than is produced |
|
Osteoporosis |
the weakening of bones due to decreased deposition of calcium. Common in the elderly. |
|
Two reasons women are particulary at risk of getting osteoporosis: |
1. Have less bone mass to begin with. Thin, petite women are at most risk 2. The reproductive hormones contribute to bone decomp,and estrogen production declines at menopause, while testosterone is produced in men throughout life, with only as slight decline as they age. |
|
Prevention of osteoporosis |
1,500mg of dietary calcium daily Weight bearing exercise - stress increases bone mass Older adults: estrogen replacement therapy and/or drug called fosamax, which blocks resorption of bone by osteoclasts |
|
Bone is a _______ _______ for _____ |
storage reservoir, minerals |
|
How much of calcium & phosphates in body is stored in bones |
99% |
|
What body functions need calcium ions (3) |
- nerve and muscle cells need calcium - many enzymes only work with calcium - needed for blood clotting |
|
Small chages in blood calcium level can cause (2) |
Heart to stop (calcium level too high) Nervous convulsions (calcium level too low) |
|
Parathyroid hormone |
increases levels of calcium in bloodstream - osteoclasts breakdown bone - calcitriol increase intestine absorbtion - kindey increase calcitriol and stimulates calcium reabsorbtion at kindeys (less calcium lost in urine)` |
|
Calcitonin |
Reduces calcium blood levels - inhibits osteoclasts (does not effect osteoblasts) - intestines stop absorbing extra calcium - suppress absorption in kidneys (more calcium in urine) |
|
Fracture |
any break in a bone |
|
Types of Fractures (8) |
1. Colles Fracture 2. Potts fracture 3. Comminuated fracture 4.Epiphyseal fracture 5. Sprial Fracture 6. Compression fracture 7. Displaced fracture 8. Transverse fracture |
|
Most common fractures when seniors fall? |
Colles Fracture, Hip Fracture |
|
Type of fracture only occurs in children |
Greenstick fracture |
|
Physician that deals with the correction of deformities of bones: |
Orthopedist |
|
Fractures are broadly categorized as: (2) |
closed (simple), open (compound) |
|
Closed fracture |
- does not protrude through the skin |
|
Open Fracture |
broken ends of bone stick out through skin. Are more dangerous than closed fractures due to the possibility of infection and uncontrolled bleeding. |
|
Three treatments of bone fractures |
1. Realignment of the bone fragments (reduction)a. closed reduction - manual manipulation is enough b. open reduction - surgery is required with screws, plates, wires, rods 2. Immobilization to maintain realignment - cast, sling, splint, bandage, etc. 3. Restoration of function - happens with time and may require physiotherapy |
|
Repair of Fracture (4) |
1. Formation of a fracture hematoma that closes off the injured blood vessels. Inflammation occurs in response to dead bone cells, and phagocytes and osteoclasts remove dead or damaged tissue and microbes. 2. Formation of a callus. Cells of the peristeum and endosteum activate and migrate into the fracture zone. External callus of cartilage and bone encircle the bone at level of fracture. Internal callus of spongy bone also forms within the marrow cavity 3. Osteoblasts replace the cartilage of the external callus with spongy bone (cast would be removed at this stage) 4. Bone remodelling - osteoclasts and blasts remodel the calluss until the bone regains its original shape. May last 4 months to well over a year. |
|
Achondroplasia |
- Little people - different protions due to unusual cartilage formation.99% of case, fibroblast growth factor receptor has a single mutation |
|
Rickets |
child has abnormal bone formation resulting from inadequte calcium in bones. Bones are soft and bendable and may have bow legs. Vitamin D lacking. |
|
Osteomalacia |
adult version of rickets. does not result in loe bowing but similar to rickets and treat in similar fashion. Common in countries where women fully cover their body (no sunlight) |
|
Gigantism |
bone grow longer as a child |
|
Acromegaly |
bones grow longer later in life |
|
Tall man in the world |
Robert Wadlow - 8'11" died at 22yrs |
|
Pituitary Dwarfism |
short bones but proportional |
|
Cleft Palate |
a split of opening in the bony plate or roof of the mouth. Occurs when the maxillary bones and palatine bones do not fuse properly. Hard to nurse if baby has because of extra air. |
|
Marfan's Syndrome |
limbs are extremely long and slender, results from excessive catilage formation at the epiphyseal plates. Defective elastic fibers in connective tissue is also present in other body organs, and these patients have weakened blood vessels |
|
Spina Bifida |
congenital defect of the vertebral column where vertebrae do not align properly and the spinal cord may protrude through openings between adjacent vertebrae. Research has shown that taking folic acid supplements during pregnancy reduce the risk of having a baby with a birth defect like spina bifida. |
|
Scoliosis |
Lateral curvature of the spine/ Idiopathic |