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Problem L2.1
Explain why a person who is wheelchair-bound or bed-bound often has very low bone mass, especially in his or her legs.
Problem L2.2
How could diseases of the kidney, skin, and/or intestines cause diseases of the bone?
Problem L2.3
How could a disease that affects primarily cartilage impact bone growth and bone formation?
Problem L3.1
It used to be common practice in surgical fracture repair to strip and remove the periosteum. Now, however, surgeons take great care to avoid damaging the periosteum. Explain why, and describe what would likely happen to bone healing with the periosteum missing.
Problem L3.2
Explain why young men who take anabolic steroids (which mimic the actions of testosterone) often display stunted growth and have an overall shorter stature.
Problem L3.3
Lucy Dupre is a 2-year-old girl living in northern Canada. You notice that her growth seems abnormally slow and she has exhibited signs of weakened bones, including fractures. Her parents admit they have not supplemented her diet with vitamin D, as they feel that any supplementation is 'unnatural' and 'not organic.' Explain why Lucy is having problems with her bones and bone growth.
Problem L3.4
Fouz Akkad is a 6-year-old girl who has been diagnosed with a rare genetic defect in which her lysosomes are unable to maintain an acidic pH. What are lysosomes? Why do lysosomes require an acidic pH? How will this affect the ability of certain bone cells to function? What consequences will this disease have on Fouz's bones?
Problem L2.2
Explain how abnormal bone structure could affect muscle function.
Problem 2
Match the following terms with the correct definition.
____Long bone
____Epiphysis
____Nutrient artery
____Flat bone
____Short bone
____Periosteum
____Diaphysis
____Medullary cavitya.
a. Main source of blood to the medullary cavity
b. Membrane surrounding the bone
c. Bone that is about as wide as it is long
d. Shaft of a long bone
e. Bone that is longer than it is wide
f. Canal running down the center of the diaphysis
g. End of a long bone
h. Bone that is broad and thin
Problem 3
Explain the differences between red bone marrow and yellow bone marrow.
Problem 4a
Mark the following statements about bone tissue as true or false. If a statement is false, correct it to make a true statement.
a. The primary mineral in the inorganic matrix is hydroxyapatite.
Problem 4b
Mark the following statements about bone tissue as true or false. If a statement is false, correct it to make a true statement.
b. The inorganic matrix of bone is solely responsible for the strength of bone tissue.
Problem 4c
Mark the following statements about bone tissue as true or false. If a statement is false, correct it to make a true statement.
c. Collagen fibers are one of the predominant parts of the inorganic matrix.
Problem 4d
Mark the following statements about bone tissue as true or false. If a statement is false, correct it to make a true statement.
d. The collagen fibers of bone help it to resist torsion and tension.
Problem 4e
Mark the following statements about bone tissue as true or false. If a statement is false, correct it to make a true statement.
e. Osteoblasts are responsible for bone resorption, and osteoclasts are responsible for bone deposition.
Problem 4f
Mark the following statements about bone tissue as true or false. If a statement is false, correct it to make a true statement.
f. Osteocytes are mature and less active osteoblasts that have become surrounded by bone ECM.
Problem 5
The subunit of compact bone is the _____ . It consists of rings of bone matrix called ______that surround a structure called the______ that contains blood vessels and nerves. Other structures called _______also contain blood vessels and nerves. Osteocytes are housed in_____and communicate via_______.
Problem 6
The branching pieces of bone in spongy bone are called:
a. Lamellae
b. Lacunae
c. Osteoclasts
d. Trabeculae
Problem 7
Which bones form via intramembranous ossification?
a. Irregular bones
b. Certain flat bones
c. Long bones
d. Short bones
e. More than one of the above
Problem 8
Of the following statements, identify those that are properties of intramembranous ossification, endochondral ossification, or both.
a. The bone is formed via a hyaline cartilage model.
b. Bone tissue forms from ossification centers.
c. Bone forms from within a mesenchyme membrane.
d. The early spongy bone is formed, after which the early compact bone develops.
e. The original primary bone is replaced with secondary bone.
f. A bone collar forms, followed by the early spongy bone.
Problem 9
What is the difference between a primary and secondary ossification center in a long bone?
Problem 10
The part of the epiphysis that does not ossify during a person's lifetime is the:
a. Articular surface
b. Secondary ossification center
c. Diaphyseal notch
d. Nutrient foramen
Problem 11
Long bones grow in length from the:
a. Diaphyseal line
b. Epiphyseal line
c. Epiphyseal plate
d. Medullary cavity
Problem 12
Correctly order the following steps of bone growth in length by placing a 1 by the first step, a 2 by the second step, and so on.
Calcified cartilage is replaced with bone in the zone of ossification.
Chondrocytes in the zone of proliferation divide by mitosis.
Chondrocytes enter the zone of calcification and die as their matrix calcifies.
Chondrocytes enlarge and cease dividing.
Problem 13a
Explain the effect that the following hormones have on the growth of bone tissue:
a. Growth hormone
Problem 13b
Explain the effect that the following hormones have on growth of bone tissue:
b. Testosterone
Problem 13c
Explain the effect that the following hormones have on the growth of bone tissue:
c. Estrogen
Problem 14
Bone deposition is carried out by_____, which secrete the____ of the ECM by exocytosis. They facilitate the formation of the______of the ECM by secreting_____filled with calcium ions, enzymes, and ATP. Bone resorption is carried out by______ , which secrete_____and_____from their ruffled border.
Problem 15a
Mark the following statements as true or false. If a statement is false, correct it to make a true statement.
a. Bone resorption is triggered by pressure placed on the bone.
Problem 15b
Mark the following statements as true or false. If a statement is false, correct it to make a true statement.
b. Bone deposition is triggered by tension placed on the bone.