Chapter 7- Bones & Bone Tissue

Question 1

Bone Functions

Answer 1

Shape
Support
Protection
Movement
Electrolyte balance
Blood production
Acid-base balance

Question 2

What are the four classifications of bones?

Answer 2

Flat Bones
Long Bones
Irregular Bones
Short Bones

Question 3

Diaphysis

Answer 3

Part of Large Bone:
Hollow cylinder made of compact bone; gives the bone strength

Question 4

Articular cartilage

Answer 4

Part of Large Bone:
Covers the epiphysis; eases the movement of the bone within a joint

Question 5

Medullary cavity

Answer 5

Part of Large Bone:
Central, hollow portion

Question 6

Endosteum

Answer 6

Part of Large Bone:
Epithelial membrane lining the medullary cavity

Question 7

Red bone marrow

Answer 7

Part of Large Bone:
Fills the medullary cavity in children; in adults, most marrow has turned to yellow marrow

Question 8

Periosteum

Answer 8

Part of Large Bone:
A dense, fibrous membrane covering the diaphysis; some of the fibers of the periosteum penetrate the bone, whereas other fibers weave together with the fibers of tendons to ensure a strong connection between muscle and bone; the periosteum contains bone-forming cells and blood vessels, making it crucial for bone survival

Question 9

Epiphyseal plate

Answer 9

Part of Large Bone:
The layer of cartilage separating the epiphysis from the diaphysis at the ends of a long bone in growing children (When growth stops, it is replaced with an epiphyseal line.)

Question 10

Which of the following are functions of bone? Choose all that apply.
a. Electrolyte balance
b. Blood production
c. Acid-base balance
d. Regulation of blood glucose

Answer 10

Correct answer: A, B, C
Rationale:
Bone plays no role in the regulation of blood glucose levels.

Question 11

What do Osteoblasts do?

Answer 11

Help form bone

Question 12

What do Osteoclasts do?

Answer 12

Dissolve unwanted bone

Question 13

What are Osteocytes?

Answer 13

Are mature osteoblasts embedded in hardened bone matrix

Question 14

Bone Characteristics

Answer 14

Unique because of its matrix, which is hard and calcified
Highly resistant to stretching forces (tensile strength)
Resists squeezing forces (compressional strength)
Lacks ability to resist twisting (torsional strength)

Question 15

Factors Affecting Bone Growth

Answer 15

Heredity
Nutrition
Hormones
Exercise

Question 16

Heredity

Answer 16

Every individual inherits a set of genes that determines his maximum height potential.

Question 17

Nutrition

Answer 17

Children who are malnourished grow very slowly and may not reach their full height, regardless of their genetic potential. Nutrients necessary for proper bone growth include calcium, phosphorus, and vitamins D, C, and A.

Question 18

Hormones

Answer 18

Hormones that contribute to proper bone growth include growth hormone, thyroxine, parathyroid hormone, insulin, and the sex hormones estrogen and testosterone.

Question 19

Exercise

Answer 19

Without adequate physical stress in the form of weight-bearing exercise (which includes walking), bone destruction will outpace bone growth.

Question 20

Two types of bone tissue

Answer 20

Compact & Spongy

Question 21

Compact Bone

Answer 21

Forms shafts of long bones and surfaces of other bones
Compact bone is dense and solid.

Question 22

Spongy Bone

Answer 22

Found in ends of long bones and middle of other bones
Spongy bone is always surrounded by compact bone.

Question 23

What is the basic structural unit of bone?

Answer 23

Osteon
Rationale:
Canaliculi are microscopic passageways that connect lamellae.
An osteocyte is a bone cell.

Question 24

Bone Marrow

Answer 24

a type of soft tissue that fills the medullary cavity of long bones and the spaces of spongy bone.

Question 25

Red Bone Marrow

Answer 25

charged with producing red blood cells. Nearly all of a child’s bones contain red bone marrow. In an adult, red bone marrow can only be found in the ribs, sternum, vertebrae, skull, pelvis, and the upper parts of the humerus (arm) and femur (thigh). All other bones contain yellow marrow.

Question 26

Yellow Bone Marrow

Answer 26

replaces red marrow over time. The cells of yellow marrow are saturated with fat and no longer produce blood cells. In cases of severe, chronic blood loss or anemia, yellow marrow can change back into red marrow.

Question 27

Two Types of Bone Development

Answer 27

Intramembranous ossification: Ossification of fibrous connective tissue (skull and face) Endochondral ossification: Ossification of cartilage (long bones)

Question 28

Bone Matrix

Answer 28

non-living, extracellular substance that makes up the majority of bone tissue. It provides structural support and strength to bones. Inorganic matrix: Primarily composed of calcium hydroxyapatite crystals, which provide rigidity and compressive strength. Organic matrix: Consists of collagen fibers, proteoglycans, and other non-collagenous proteins. Collagen provides tensile strength and flexibility.

Question 29

Bone Growth

Answer 29

Bone lengthening occurs at the epiphyseal plate for a fixed period. Bone widening continues throughout the life span.

Question 30

Bone Remodeling

Answer 30

Process in which bone cells continually destroy old bone (resorption) and deposit new bone (ossification).

Question 31

Childhood Bone Remodeling

Answer 31

Bone creation outpaces resorption

Question 32

Middle Adulthood Bone Remodeling

Answer 32

Creation and resorption in balance

Question 33

After age 40 Bone Remodeling

Answer 33

Bone loss increases and formation slows, causing bones to weaken

Question 34

What are the 5 bone fractures?

Answer 34

Simple, Compound, Greenstick, Comminuted, Spiral

Question 35

Simple fracture

Answer 35

Bone remains aligned and surrounding tissue is intact.

Question 36

Compound fracture

Answer 36

Bone pierces the skin. Damage to surrounding tissue, nerves, and blood vessels may be extensive. Increased risk for infection because of open wound.

Question 37

Greenstick fracture

Answer 37

Similar to when a green stick breaks: Incomplete. Typically occurs in young children because their bones are softer and more flexible.

Question 38

Comminuted fracture

Answer 38

Bone breaks into pieces. Tend to occur with high-impact trauma, such as car accident.

Question 39

Spiral fracture

Answer 39

Results from twisting forces. The jagged bone ends make this type of fracture difficult to reposition.

Question 40

Fracture Repair

Answer 40

1) Initial hematoma transforms into granulation tissue. 2) Granulation tissue transforms into a soft callus. 3)A hard callus forms around the fracture. 4)Remodeling replaces the callus tissue with bone.

Question 41

A fetus’s first skeleton is composed primarily of: a. epithelial tissue. b. osseous tissue. c. cartilage. fd.ibrous connective tissue.

Answer 41

C Rationale: Epithelial tissue is not involved in the formation of bone. Osseous tissue is bone. While parts of the skull begin as fibrous connective tissue, most evolve from cartilage.