Test #3 Flashcards
What are the functions of the 💀?
- 💉 formation
- acid-base balance
- electrolyte balance
- protection
- movement
- support
What are general features of types of 🦴 ?
Flat-
•thin curved/wide plates
•protect soft organs
Long-
•longer than wide
•rigid levers acted on by 💪🏼
Short-
•equal in width/length
•glide across each other in multiples directions (limited movement)
Irregular-
•elaborate shapes that don’t fit in categories
What are general features of bones?
- compact bone
- diaphysis (shaft)
- medullary cavity (marrow cavity)
- epiphysis
- 🧽 🦴 (cancellous 🦴)
- articular cartilage
- nutrient foramina
- periosteum
- endosteum
- epiphyseal plate
What are the 4 types of 💉 cells?
- osteogenic cells-create osteoblasts & osteocytes
- osteoblasts-builds/forms bone
- osteocytes-osteoblasts that get trapped in matrix they deposited
- osteoclasts-dissolve 🦴 to increase calcium in 💉flow
What’s the matrix made of?
•1/3 = organic matter (made by osteoblasts)
-collagen
-carbohydrate-protein complexes (glycosaminoglycans, proteoglycans, glycoproteins)
•2/3 = inorganic matter
-85% hydroxyapatite (crystallized calcium phosphate 🧂)
-10% calcium carbonate
-other minerals (fluoride, sodium, potassium, magnesium)
What is compact 🦴?
- outer shell of long 🦴
- dense osseous tissue
- surrounds medullary/marrow cavity
What is spongy 🦴?
- looser osseous tissue
- spicules (🦴 slivers)
- trabeculae (thin 🦴 plates)
- spaces filled w/red 🦴 marrow
- few osteons
- no central canals
- provides strength w/minimal weight
What is 🦴 marrow?
•soft tissue occupying marrow cavity of long bone & small spaces in 🧽 🦴 trabeculae
•red marrow (myeloid tissue)
-in every kid’s bone
-hemopoietic tissue (produces 💉 cells ; made of many tissues)
-some adult 🦴(pelvic girdle, skull, vertebrae, ribs sternum, humerus/femur proximal heads)
•yellow marrow in adults
-used to be red marrow
-doesn’t produce blood
Intramembranous ossification
•produces flat 🦴 of skull & clavicle
Endochondral ossification
•produces most 🦴 beside flat skull 🦴
Calcium homeostasis
- depends on balance between dietary intake, urinary/fecal loss, exchanges between osseous tissue
- hypocalcemia vs. hypercalcemia
- regulated by hormones (calcitonin, calcitriol, PTH)
Calcitriol
- form of Vitamin D
- produced by skin, liver, kidneys
- raises 💉 calcium concentration
- needed for bone deposition
Calcitonin
- produced by C cells (clear cells) of thyroid gland
* released when 💉 calcium concentration’s high
Parathyroid Hormone (PTH)
- released by parathyroid glands (adhered time posterior surface of thyroid glands)
- released when 💉 calcium’s low
What are some 🦴 disorders?
- rickets (lack of Vitamin D)
- osteoporosis
- osteogenesis imperfecta (brittle 🦴disease)
