Chapter 6 - REVIEW - Osseous Tissue And Bone Structure

Question 1

Blood cell formation occurs in…

Answer 1

Red bone marrow

Question 2

2/3 the weight of bone is accounted for by….

Answer 2

Crystals of calcium phosphate

Question 3

The membrane found wrapping the bones, except at the joint cavity, is the….

Answer 3

Periosteum

Question 4

What are the 5 primary functions of the skeletal system?

Answer 4

-Support
-Storage of minerals and lipids
-Blood cell production
-Protection
-Leverage

Question 5

List the organic and inorganic components of bone matrix

Answer 5

Inorganic - hydroxyapatite crystals
Organic - collagen

Question 6

The basic functional unit of compact bone is the Haversian system or ___

Answer 6

Osteon

Question 7

The vitamins essential for normal adult bone maintenance are vitamins __ and ___

Answer 7

C and D

Question 8

What are the 2 hormones that coordinate the storage, absorption, and excretion of calcium ions?

Answer 8

Calcitonin and the parathyroid hormone

Question 9

The presence of an epiphyseal line indicates…

Answer 9

Epiphyseal growth has ended

Question 10

What is the PRIMARY reason that osteoporosis accelerates after menopause in women??

Answer 10

Reduced levels of circulating estrogens

Question 11

The non pathological loss of bone that occurs with aging is called…

Answer 11

Osteopenia

Question 12

List the 4 distinctive cell populations of osseous tissue

Answer 12

Osteocytes
Osteoblasts
Osteoclasts
Osteoprogenitor cells

Question 13

Why are stresses or impacts to the side of the shaft in a long bone more dangerous than stress applied to the long axis of the shaft?

Answer 13

The osteons are aligned parallel to the long axis of the shaft, which does not bend when forces are applied to either end. Stresses on impacts to the side of the shaft can lead to a fracture

Question 14

What are the primary parts of a typical long bone?

Answer 14

-diaphysis (shaft)
-epiphysis
-epiphyseal cartilage/line
-articular cartilage
-medullary canal
-periosteum
-endosteum

Question 15

What is th primary difference between endochondral ossification and intramembranous ossification?

Answer 15

In intramembranous ossification, bone replaces mesenchyme or fibrous connectiove tissue.
In endochondral ossification, bone replaces a cartilage model

Question 16

What nutritional factors are essential for normal bone growth and maintenance?

Answer 16

Calcium salts, phosphate salts, vitamins A, C, and D3

Question 17

What hormonal factors are necessary for normal bone growth and maintencae?

Answer 17

Calcitriol, growth hormone, thyroxine, estrogen (females), androgens (in males), and parathyroid hormone (PTH)

Question 18

Which 3 organs interact to assist in the regulation of calcium ion concentration in body fluids?

Answer 18

The bones, the intestinal tract, and the kidneys

Question 19

What major effects of parathyroid hormone oppose those of calcitonin?

Answer 19

Parathyroid hormone stimulates osteoclast activity, increases the rate of intestinal absorption of calcium ions, and decreases the rate of excretion of calcium ions by the kidneys

Question 20

If spongy bone has no osteons, how do nutrients reach the osteocytes?

Answer 20

By nutrients diffusing along canaliculi that open onto the surface of the trabeculae

Question 21

Why do extended periods of inactivity cause degenerative changes in the Skelton?

Answer 21

The lack of stress during inactivity leads to the removal of calcium salts from bones. Up to 1/3 of bone mass can be lost in this manner, causing bones to become thin and brittle

Question 22

What are the functional relationships between the skeleton on the one hand, and the digestive and urinary systems on the other?

Answer 22

The digestive and urinary systems (kidneys) play important roles in providing calcium and phosphate minerals needed for bone growth. In return, the Skelton provides protection and acts as a reserve of calcium, phosphate, and other minerals that can compensate for changes in the dietary supply of these ions

Question 23

Why would a physician be concerned about the growth patterns of a young child request an X-ray in his hand?

Answer 23

There are many long bones in the hand, each of which has an epiphyseal cartilage (plate). Measuring the width of these plates will provide clues to the hormonal control of growth in the child

Question 24

Why does a second fracture in the same bone tend to occur at a site different from that of the first fracture?

Answer 24

Once a bone fracture has been repaired, the bone tends to be stronger and thicker than normal at the fracture site

Question 25

The process of bone growth at epiphyseal cartilage is similar to…..

Answer 25

Endochondral ossification

Question 26

How might bone markings be useful in identifying the remains of an individual who was killed and shot years ago?

Answer 26

Bone markings give clues as to the size, age, sex, and general appearance of an individual

Question 27

10 year old sally falls and breaks her right leg. The dr tells the parents that the proximal end of the tibia where the epiphysis meets the diaphysis is fractured. The fracture is properly set and eventually heals. When she is 18, sally learns that her right leg is 2cm shorter than her left. What might account for this difference?

Answer 27

The fracture might have damaged the epiphyseal cartilage in Sally’s right leg. Even though the bone healed properly, the damaged leg did not produce as much cartilage as the undamaged leg, the result is a shorter bone on the side of the injury

Question 28

What condition would you possibly observe in a child who is suffering from rickets?

Answer 28

Bowed legs

Question 29

Frank does not begin puberty until he is 16. What effect would you predict this will have on his stature?

Answer 29

Frank will probably be taller than if he had started puberty earlier

(The plates will be open longer?)

Question 30

In physical anthropology, cultural conclusions can be drawn from a thorough examination of the skeletons of ancient peoples. What sort of clues might bones provide as to the lifestyles of those individuals?

Answer 30

The matrix of bone will absorb traces of minerals from the diet. A diet rich in calcium and vitamin B will produce denser bones than a diet lacking these. Cultural practices such as the binding of appendages or the wrapping of infant heads will result in misshapen bones. Heavy muscular activity will result in larger bone markings, indicating an athletic or physically demanding lifestyle