Bone Formation and Development

Question 1

Adult bones are composed of __ percent protein (called____),____ percent minerals (including___,___,and____), and ____ percent___.

Answer 1

30 ; ossein

45

calcium, phosphorus, and magnesium

25

water

Question 2

Minerals give the bone____ and_____.

Answer 2

strength

hardness

Question 3

At birth, bones are(soft or hard?) and ____ because of _____ in their structure.

Answer 3

Soft

pliable

cartilage

Question 4

As the body grows, (younger or older?) cartilage gradually is replaced by _______

Answer 4

Older

hard bone tissue.

Question 5

Minerals in the bones (increase or decrease?) with age, causing the bones to become more ____ and____

Answer 5

Increase

brittle

easily fractured.

Question 6

EMBRYOLOGY of bone

-In the early stages of embryonic development, the embryo’s skeleton consists of ____ membranes and____ cartilage.

Answer 6

fibrous

hyaline

Question 7

By the ____ or ____ week of embryonic life, the actual process of bone development,ossification(______), begins.

Answer 7

sixth

seventh

osteogenesis

Question 8

There are two osteogenic pathways:____ ossification and______ ossification

Answer 8

intramembranous

endochondral

Question 9

Mature bones differ from one another based on the process of osteogenesis that made it
T/F

Answer 9

F

in the end, mature bone is the same regardless of the pathway that produces it.

Question 10

Intramembranous Ossification of bone
-Duringintramembranous ossification, _____ and _____bone develops directly from_______(differentiated or undifferentiated?) connective tissue.

Answer 10

compact and spongy

sheets of mesenchymal

undifferentiated

Question 11

The ___ bones of the____, most of the_____ bones, and the ______ are formed via intramembranous ossification.

Answer 11

flat; face

Cranial

clavicles (collarbones)

Question 12

The process of intramembraneous ossification begins when mesenchymal cells in the embryonic skeleton ______and begin to_____
-Some of these cells will differentiate into____, while others will become _____ (_____) cells and then ______.

Answer 12

gather together

differentiate into specialized cells

capillaries

osteogenic; bone producing

osteoblasts

Question 13

Although clusters of osteoblasts will ultimately be spread out by the______, early osteoblasts appear in a cluster called an_____.

Answer 13

formation of bone tissue

ossification center

Question 14

Intramembranous ossification beginsin _____during fetal development and continues on into _____.

Answer 14

utero

adolescence

Question 15

-At birth, the ____ and ____are not fully ossified nor are the_____(____) closed.

And This allows the ____ and____ to deform during passage through the birth canal.

Answer 15

skull and clavicles

junctions between the skull bone

Sutures

skull and shoulders

Question 16

The last bones to ossify via intramembranous ossification are the ______, which reach their adult size at the ____ of the _____

Answer 16

flat bones of the face

end

adolescent growth spurt

Question 17

Endochondral Ossification

-Inendochondral ossification, bone develops by______

Answer 17

replacinghyaline cartilage.

Question 18

Cartilage becomes bone.

T/F

Answer 18

F

Cartilage does not become bone.

Question 19

cartilage serves as a ____ to be_____ by new bone.

Answer 19

template

completely replaced

Question 20

Which takes longer, intramembranous ossification or Endochondral ossification?

Answer 20

Endochondral ossification takes much longer than intramembranous ossification.

Question 21

Bones at the base of the skull form via _____ ossification.

Answer 21

endochondral

Question 22

long bones form via _____ ossification.

Answer 22

endochondral

Question 23

In a long bone, for example, at about __to__ weeks after conception, some of the mesenchymal cells differentiate into____ (____cells) that form the ______skeletal precursor of the bones

Answer 23

6 to 8

chondroblasts

cartilage

hyaline cartilaginous

Question 24

Hyaline cartilage is a (flexible or rigid?) , (solid or liquid?)matrix produced by _____ and consists of _____,______,_____, and____.
-As the matrix surrounds and isolates_____, they are called ______.

Answer 24

Flexible

Semi-solid

chondroblasts

hyaluronic acid; chondroitin sulfate; collagen fibers; water

chondroblasts; chondrocytes

Question 25

cartilage is (vascular or avascular?)

Answer 25

Avascular

Question 26

cartilage is avascular, meaning that it has no blood vessels supplying nutrients and removing metabolic wastes. -All of these functions are carried on by _____ from vessels in the surrounding _____, a membrane that covers the cartilage

Answer 26

diffusion through the matrix perichondrium

Question 27

Growth of Bone - Long bones continue to lengthen, potentially until _____, through the addition of bone tissue at the ______. - They also increase in width through _____ growth.

Answer 27

adolescence epiphyseal plate appositional

Question 28

Lengthening of Long Bones -Chondrocytes on the _____ side of the epiphyseal plate are going to ____; one cell remains undifferentiated near the _____, and one cell moves toward the_____.

Answer 28

epiphyseal divide epiphysis diaphysis

Question 29

Lengthening of Long Bones The cells, which are pushed from the _____, mature and are destroyed by_____. -This process replaces cartilage with bone on the _____ side of the plate, resulting in a lengthening of the bone.

Answer 29

epiphysis calcification diaphyseal

Question 30

Long bones stop growing at around the age of ____ in females and the age of____ in males in a process called _______ - During this process, ____ cells stop dividing and all of the ____ is replaced by____ - The ____ plate fades, leaving a structure called the _____ or _____, and the ____ and ____ fuse.

Answer 30

18 21 epiphyseal plate closure cartilage; cartilage;bone epiphyseal epiphyseal line or epiphyseal remnant epiphysis and diaphysis

Question 31

Thickening of Long Bones - Appositional growth is the increase in the _____ of bones by the addition of bony tissue at the ____ of bones. - _____at the bone’s___ surface secrete _____, and____ on the____ surface break down bone.

Answer 31

diameter surface Osteoblasts; outer ; bone matrix osteoclasts; inner

Question 32

In thickening of long bones The osteoblasts differentiate into______.

Answer 32

osteocytes

Question 33

A balance between osteoblasts and osteoclasts processes allows the bone to ____ without becoming____.

Answer 33

thicken too heavy

Question 34

Bone Remodeling and Repair: | It involves the processes of bone deposition by ___ and bone resorption by _____.

Answer 34

osteoblasts osteoclasts

Question 35

Bone renewal continues after birth and stops at adolescence T/F

Answer 35

F Reaches adulthood

Question 36

Bone remodeling is the _____ tissue by ____ tissue.

Answer 36

replacement of old bone new bone

Question 37

Normal bone growth requires vitamins __,___,and___ plus minerals such as ___,___,and___

Answer 37

D, C, and A, calcium, phosphorous, and magnesium.

Question 38

Hormones such as _____ hormone, ____ hormone, and_____ are also required for proper bone growth and maintenance.

Answer 38

parathyroid growth calcitonin

Question 39

Bone remodeling allows bones to adapt to stresses by becoming____ and____ when subjected to stress.

Answer 39

thicker stronger

Question 40

Bones that are not subject to normal stress, for example when a limb is in a cast, will begin to____

Answer 40

lose mass.

Question 41

A fractured or broken bone undergoes repair through four stages: (1)Blood vessels in the broken bone____and ____, resulting in the formation of____, or a____, at the site of the break.The severed blood vessels at the broken ends of the bone are sealed by the ___ process, and bone cells that are deprived of nutrients begin to___.

Answer 41

tear and hemorrhage clotted blood Hematoma Clotting die

Question 42

A fractured or broken bone undergoes repair through four stages: (2)Within ___ of the fracture,____ grow into the hematoma, and phagocytic cells begin to ________Though fragments of the blood clot may remain, ____ and ____enter the area and begin to reform bone.Some bone ____ may also appear at this point.

Answer 42

days capillaries clear away the dead cells. fibroblasts and osteoblasts spicules

Question 43

Fibroblasts produce ____that_____, and osteoblasts start to———.

Answer 43

collagen fibers connect the broken bone ends form spongy bone

Question 44

The repair tissue between the broken bone ends is called the_____, as it is composed of both _____ and _____

Answer 44

fibrocartilaginous callus hyaline and fibrocartilage.

Question 45

A fractured or broken bone undergoes repair through four stages: (3)The fibrocartilaginous callus is converted into a _____ of ____ bone.It takes about ____for the broken bone ends to be firmly joined together after the fracture.This is similar to the _____ formation of bone, as cartilage becomes ossified; osteoblasts, osteoclasts, and bone matrix are present.

Answer 45

bony callus spongy two months endochondral

Question 46

A fractured or broken bone undergoes repair through four stages: (4) The bony callus is then remodelled by___and ___, with excess material on the (interior or exterior?) of the bone and within the ______ being removed. ______bone is added to create bone tissue that is similar to the original, unbroken bone.But note that This remodeling can take ___, and the bone may remain ____ for years.

Answer 46

osteoclasts and osteoblasts Exterior medullary cavity Compact many months uneven

Question 47

Bone turnover rates are quite (high or low?), with ___ to___ percent of bone mass being recycled every ____.

Answer 47

High Five to seven week

Question 48

bone turnover rate are different in different areas of the skeleton but the same in different areas of a bone. T/F

Answer 48

F Differences in bone turnover rate exist in different areas of the skeleton and in different areas of a bone.

Question 49

the bone in the ___ of the femur may be fully replaced every ____ whereas the bone along the ____ is altered much more (slowly or rapidly?)

Answer 49

head six months, shaft Slowly