Flashcards in Lecture Test 3 Deck (109)
List the functions of the skeletal system.
Blood cell production
Leverage (force of motion)
Shapes of bones
What is the composition of bone matrix? What substance comprises
about two thirds of the matrix? What percentage do cells contribute?
Bone matrix is 2/3
Collagen: Ca(PO4)2 is 1/3
Cells contribute 2%
What is the histological difference between compact bone and spongy
bone? Which one has osteons (Haversian systems)? Which one
Osteons (Haversian system): compact bone (looks like bulls eye)
Bone marrow: spongy bone (looks spiky with spaces)
6. What is the difference between endochondral and intramembranous
ossification? Which type is most common in humans?
Endo: in cartilage, develops first as hyaline cartilage then ossifies into bone. Most common in humans.
Intra: dermal ossification, gives rise to clavicle and mandible
7. What effect does exercise have on bone?
Increases bone density and mass
8. How do bones grow in length? What two hormones control growth at the epiphyseal plate?
Length is added at the epi plates where cartilage is laid down then later changes into bone.
Hormones: HGH and thyroxine
How do appositional growth and bone remodeling take place?
Must break down bone with osteoclast then rebuild with osteoblast to widen or repair bone
How does bone deposition and bone destruction vary throughout life?
Early life: deposition exceeds destruction
Age 20-40: deposition equals destruction
Age 40+: destruction exceeds deposition
For what mineral is the skeleton the primary reservoir? What two
hormones control the blood level of this mineral?
Calcium, regulated by parathyroid hormone and calcitonin
How do osteopenia and osteoporosis differ?
Osteopenia: Naturally occurring bone loss with age. Does not effect function.
Osteoporosis: Severe, abnormal bone loss. Affects normal function of bone.
Name the two major divisions of the skeletal system and the major
components of each.
Skull Pectoral girdle
Vertebrae Upper extremities (arms)
Sternum Pelvic girdle
Ribs Lower extremities (legs)
Immovable joints in the skull: saggital, coronal, lambdoidal, squamous
Define Paired Cranial Bones
Parietal and temporal
(all other cranial bones are unpaired)
Define Unpaired Facial Bones
mandible and vomer
(all others are paired)
4 Skull Bones containing Paranasal Sinuses
Cranial openings in newborns aka "soft spots"
Be able to distinguish the five types of vertebrae.
12 thoracic (facets for ribs)
5 lumbar (bear most weight)
sacrum and coccyx (fused)
Hole = transverse process
What are the four normal curvatures of the vertebral column and when
do they develop?
What are the names for and location of the abnormal curvatures of the vertebral column?
Primary: during fetal life Scoliosis: lateral curvature
Secondary: when learn to walk Kyphosis: cervical curvature
Lordosis: lumbar curvature
What Forms the Ankle
Medial malleolus of tibia and
Lateral malleolus of fibula
What Forms the Brest bone
What Forms the Chin
What Forms the Collar Bone
What Forms the Forehead
What Forms the Heel
What Forms the Knee Cap
What Forms the Nasal Septum
Perpendicular plate of ethmoid
What Forms the Shoulder Blade
What Forms the Toes and Fingers