BIO 201 EXAM 2
1. Explain how the structure of a flat bone is conducive to protection: compactbone on the
inside and outside and spongy bone in the middle so the outer layer may fracture and crush
the dipole, but no harm to the inner compact bone.
2. osteoblasts: - form organic matter of matrix and helot mineralize it in responseto stress
fractures
3. osteocytes: - osteoblasts that have become trapped. reside in lacunae, con-nected via
canaliculi.
4. osteoclasts: - bone-dissolving cells, develop bone marrow by the fusion of thesame stem
cells that give rise to monocytes in blood.
5. Describe the organic components of bone: organic- collagen, glycosamino-glycans,
proteoglycans, and glycoproteins (1/3 organic)
6. describe the inorganic components of bone: inorganic- 85% hydroxapatite-crystalized
calcium phosphate salt, 10% calcium carbonate, other minerals (2/3 inorganic)
7. Explain the importance of a combination of organic and inorganic matterin bones:
provides strength and resilience.
minerals resist compression; collagen resists tension
8. Describe rickets: rickets-(in children) insufficient sunlight or vitamin D, dietarydeficiency
in calcium or phosphate, liver or kidney disease
9. Describe osteomalacia: -in adults; defective mineralization of bones
10. gelatinous marrow: -yellow marrow replaced with reddish jelly
11. intramembranous: -produces flat bones of skull and clavicle, mesenchymecondenses into
a sheet of soft tissue. osteoblasts gather on trabecular to form osteoid tissue(uncalcified bone)
12. endochondral ossification: -mesenchyme differentiates into hyaline cartilage,cartilage is
broken down, reorganized, calcified
13. Explain the significance the epiphyseal plate: - a cartilagenous material that remains as
growth plate between medullary cavity and secondary ossificationcenters in the epiphyses
14. interstitial bone growth: interstitial- bones increase in length at epiphysealplate
15. appositional bone growth: appositional- bones increase in width (mature boneonly)
16. achondroplasia: -short stature but normal sized head and trunk; spontaneousmutation
when DNA is replicated
17. pituitary dwarfism: -lack of growth hormone, short stature but normal propor-tions
18. Explain the process of bone deposition: crystallization of ions from blood; levels of
calcium and phosphate in tissues much reach a point(solubility product) before crystallization
can occur
, 19. ectopic ossification: abnormal , such as the hardening of arteries
20. List the enzymes/chemicals involved bone resorption: hydrogen ions, chlo-ride ions,
hydrochloric acid, acid phosphatase
21. List the functions of calcium: - communication between neurons, musclecontractions,
blood clotting, exocytosis. 99% IN BONES..
22. List the functions of phosphate: - component of DNA, RNA, ATP phospho-lipids and
acid-base buffers
23. hypercalcemia: -excessive lood calcium (rare), depresses nervous systemcuases muscle
weakness, sluggish reflexes , cardiac arrest.
24. hypocalcemia: -deficiency of blood calcium , causes excessive excitability of nervous
system leading to muscle spasms, tremors, or tetanus. Caused by vitaminD deficiency,
diarrhea, pregnancy, lactation
25. List the three main hormones involved in calcium homeostasis: calcitrol,calcitonin, PTH
26. calcitrol: -acts as hormone, stimulates small intestine to absorb calcium and
phosphate,promotes osteoclast activity
27. calcitonin: - secreted by thyroid gland when calcium concentration too high.reduces
osteoclasts activity , increases the # of activity of osteoblasts
28. PTH: - secreted by parathyroid glands, released when calcium level is too low.inhibits
activity of osteoblasts, stimulates osteoclast multiplication and activity
29. Explain the effects of estrogen and steroids on bones: estrogen increases bone growth;
steroids may cause premature closure of growth plate producing shortadult stature.
30. stress fractures: -a break caused by abnormal trauma to a bone
31. pathological fractures: - a break in a bow weakened by some other disease
32. closed (simple or non-displaced): - skin is not broken
33. open (compound or displaced): - bone protrudes from skin
34. Complete: - broken in 2 or more pieces
35. Incomplete: - extends only partway (pieces remain joined)
36. Greenstick: - one side bent, incomplete fracture on other
37. hairline: - fine crack
38. comminuted: - broken in3or more pieces (fragmented)
39. Linear: -parallel along the long axis of the bone
40. Transverse: - perpendicular to long axis of bone
1. Explain how the structure of a flat bone is conducive to protection: compactbone on the
inside and outside and spongy bone in the middle so the outer layer may fracture and crush
the dipole, but no harm to the inner compact bone.
2. osteoblasts: - form organic matter of matrix and helot mineralize it in responseto stress
fractures
3. osteocytes: - osteoblasts that have become trapped. reside in lacunae, con-nected via
canaliculi.
4. osteoclasts: - bone-dissolving cells, develop bone marrow by the fusion of thesame stem
cells that give rise to monocytes in blood.
5. Describe the organic components of bone: organic- collagen, glycosamino-glycans,
proteoglycans, and glycoproteins (1/3 organic)
6. describe the inorganic components of bone: inorganic- 85% hydroxapatite-crystalized
calcium phosphate salt, 10% calcium carbonate, other minerals (2/3 inorganic)
7. Explain the importance of a combination of organic and inorganic matterin bones:
provides strength and resilience.
minerals resist compression; collagen resists tension
8. Describe rickets: rickets-(in children) insufficient sunlight or vitamin D, dietarydeficiency
in calcium or phosphate, liver or kidney disease
9. Describe osteomalacia: -in adults; defective mineralization of bones
10. gelatinous marrow: -yellow marrow replaced with reddish jelly
11. intramembranous: -produces flat bones of skull and clavicle, mesenchymecondenses into
a sheet of soft tissue. osteoblasts gather on trabecular to form osteoid tissue(uncalcified bone)
12. endochondral ossification: -mesenchyme differentiates into hyaline cartilage,cartilage is
broken down, reorganized, calcified
13. Explain the significance the epiphyseal plate: - a cartilagenous material that remains as
growth plate between medullary cavity and secondary ossificationcenters in the epiphyses
14. interstitial bone growth: interstitial- bones increase in length at epiphysealplate
15. appositional bone growth: appositional- bones increase in width (mature boneonly)
16. achondroplasia: -short stature but normal sized head and trunk; spontaneousmutation
when DNA is replicated
17. pituitary dwarfism: -lack of growth hormone, short stature but normal propor-tions
18. Explain the process of bone deposition: crystallization of ions from blood; levels of
calcium and phosphate in tissues much reach a point(solubility product) before crystallization
can occur
, 19. ectopic ossification: abnormal , such as the hardening of arteries
20. List the enzymes/chemicals involved bone resorption: hydrogen ions, chlo-ride ions,
hydrochloric acid, acid phosphatase
21. List the functions of calcium: - communication between neurons, musclecontractions,
blood clotting, exocytosis. 99% IN BONES..
22. List the functions of phosphate: - component of DNA, RNA, ATP phospho-lipids and
acid-base buffers
23. hypercalcemia: -excessive lood calcium (rare), depresses nervous systemcuases muscle
weakness, sluggish reflexes , cardiac arrest.
24. hypocalcemia: -deficiency of blood calcium , causes excessive excitability of nervous
system leading to muscle spasms, tremors, or tetanus. Caused by vitaminD deficiency,
diarrhea, pregnancy, lactation
25. List the three main hormones involved in calcium homeostasis: calcitrol,calcitonin, PTH
26. calcitrol: -acts as hormone, stimulates small intestine to absorb calcium and
phosphate,promotes osteoclast activity
27. calcitonin: - secreted by thyroid gland when calcium concentration too high.reduces
osteoclasts activity , increases the # of activity of osteoblasts
28. PTH: - secreted by parathyroid glands, released when calcium level is too low.inhibits
activity of osteoblasts, stimulates osteoclast multiplication and activity
29. Explain the effects of estrogen and steroids on bones: estrogen increases bone growth;
steroids may cause premature closure of growth plate producing shortadult stature.
30. stress fractures: -a break caused by abnormal trauma to a bone
31. pathological fractures: - a break in a bow weakened by some other disease
32. closed (simple or non-displaced): - skin is not broken
33. open (compound or displaced): - bone protrudes from skin
34. Complete: - broken in 2 or more pieces
35. Incomplete: - extends only partway (pieces remain joined)
36. Greenstick: - one side bent, incomplete fracture on other
37. hairline: - fine crack
38. comminuted: - broken in3or more pieces (fragmented)
39. Linear: -parallel along the long axis of the bone
40. Transverse: - perpendicular to long axis of bone
