P9 BIOCHEMISTRY Flashcards
mention at least 2 functions of bone
- Support and attachment for muscles, ligaments, tendons, and joints
- protects internal organs
- Mineral reservoir for calcium and phosphate homeostasis
- Support blood formation
this x-ray is indicative of
Rickets
Children’s form of osteomalacia
Rickets
insufficient dietary calcium
Insufficient vitamin D fortification or insufficient exposure to sun light.
are all causes for developing
Osteomalacia
rickets signs
bowed legs, and deformities of the pelvis, ribs, and skull
Identify the disease seen
under the microscope
Osteoporosis
mention at least 2 risk factors for osteoporosis
- Female gender
- age > 70
- asian / Caucasian
- early menopause
mention at least 3 modifiable osteoporosis risk factors
- Smoking
- Alcohol abuse
- Excessive caffeine consumption
- Excessive dietary protein consumption
- Lack of dietary calcium
- Lack of sunlight exposure
causes of 2ndry osteoporosis
- Metabolic bone disease, such as hyperparathyroidism
- Neoplasia, as with multiple myeloma or metastatic carcinoma
- Malnutrition
- Drug therapy, as with corticosteroids
- Prolonged immobilization
Factors that Affect Peak Bone Mass
- Gender (M>F )
- Race (Blacks >Whites)
- Genetics
- Gonadal steroids
- Growth hormone
- Calcium intake
- Exercise
dense outer surface ofbonethat forms a protective layer around the internal cavity
Cortical / compact bone
porousbonecomposed of trabeculatedbonetissue
Trabecular / cancellous bone
the spongy tissue inside. It contains stem cells which differentiate to give rise to the different types of blood cells.
bone marrow
most prominent type composing bones
Collagen Type I
mention the 4 organic proteins composing bones
fibronectin, osteocalcin, osteopontin, osteonectin
Growth factor proteins/cytokines composing bones
TGF beta / IGF / FGF
2 inorganic salts forming hydroxyapatite.
calcium phosphate and calcium hydroxide
Mature bone cells, spiders shaped, help maintain bone tissue.
Osteocytes
Bone generating cells that Forms the matrix and collagen
Osteoblasts
bone resorption is a function of which bone cells
Osteoclasts
Differentiate to form osteoblasts
Mesenchymal stem cells
Produce growth factors for haematopoesis
Help osteoclasts to form
Mesenchymal stem cells
a lifelong process where mature bone tissue is removed from the skeleton
bone resorption
new bone tissue formation is a process known as
ossification or new bone formation
what are the 5 steps of bone remodelling cycle
activation, resorption, reversal, formation and termination
in which stage are Osteoclast precursor cells recruited from the circulation and activated
the activation stage
which phase is terminated by apoptosis of osteoclasts
Resorption phase
enzyme that generates osteoclasts pump protons
Carbonic Anhydrase II
bone resorption switches to formation happens in which phase
the reversal phase
osteoblasts synthesize and secrete a type 1collagen-rich osteoid matrix. & osteoblasts play a part in regulating osteoid mineralization is known to be part of which phase
formation phase
is a factor through which osteoblasts
regulate osteoclasts, and bone formation
is coupled to bone resorption
RANKL
During bone remodeling, mature osteoblasts synthesize bone-specific proteins , mention at least 2 of them
-Osteocalcin
- Bone-specific alkaline phosphatase
- Procollagen-I extension peptide
Bone turnover markers are physiologically elevated during
childhood, growth, and during fracture healing
Local factors that affect bone remodelling
- Cytokines
- Local stress
- pH
- Temperature
- PO2
General factors that affect bone remodelling
- Genetics
- Calcium availability
- Sex steroids
- Thyroxine / GH
- Mechanical usage
