More About Bones

Question 1

What are the basic funtions of the bones?

Answer 1

Bones

• Support the body
• Protect the body
• Allow movement to the body
• Storage
• Blood cell formation

Question 2

Referring to the support function of the bones, what would happen if we did not have bones?

Answer 2

Without bones, we would not be able to stand up straight, stand up at all.

Question 3

Referring to the protection function of the bones, what would happen if we did not have bones?

Answer 3

Without bones, important organs (like the heart and lungs) would not be protected and could be easily damaged by something external.

Question 4

Referring to the movement functions of the bones, what would happen if we did not have bones?

Answer 4

We would not be able to move. Muscles contract and stretch to move the bones.

Question 5

Referring to the storage function of the bones, what would happen if we did not have bones?

Answer 5

There would be nothing to store important minerals like calcium and phosphorus, as well as, bone marrow (red and yellow)

Question 6

What is the difference between the yellow and red bone marrow?

Answer 6

Yellow marrow is found in the medullary cavity and stores fat. Red marrow is found in the cavities of many bones and is critically important for hematopoiesis.

Question 7

What is hematopoiesis?

Answer 7

blood cell formation

Question 8

Referring to the hematopoiesis function of the bones, what would happen if there were no bones?

Answer 8

There would be no red marrow to produce blood cells

Question 9

What do blood cells do?

Answer 9

Our blood cells deliver oxygen to tissues throughout the body, and transport waste in the form of carbon dioxide to the lungs so we can breathe the waste out.

Question 10

Where is red marrow found?

Answer 10

Red marrow is found in flat bones and at the end on long bones.

Question 11

What are the structural building blocks of bones?

Answer 11

Cells

Question 12

What are osteocytes?

Answer 12

mature bone cells

Question 13

What is bone tissue made of?

Answer 13

60%-70% of the bone weight comes from mineral content (usually calcium carbonate and calcium phosphate)

30%-40% of the bone weight comes from collagen

Question 14

What is collagen?

Answer 14

A protein that provides bone’s flexibility, and water.

Question 15

Why do the bones of children tend to be more flexible than the bones of adults?

Answer 15

Children have more collagen and water content in their bones than adults.

Question 16

What is cortical tissue?

Answer 16

a dense tissue with a high mineral content. it is very strong, not too flexible, and is the outer surface of all bones.

Question 17

What is trabecular tissue?

Answer 17

a porous tissue with a low mineral content, low stength, very flexible, and is usually found in places like the verebrae and wrists.

Question 18

What are the four types of shapes a bone can be classified by?

Answer 18

long, short, flat, and irregular

Question 19

Name an example of a bone that will fit into each bone shape classification.

Answer 19

• long - humerus
• short - metacarpal
• flat - sternum
• irregular - hips

Question 20

What are the epiphyses and diaphysis of a long bone?

Answer 20

Question 21

Where are the periosteum and the endosteum of a long bone?

Answer 21

The periosteum surround the diaphysis and contains blood vessels and nerves, and the endosteum lines the medullary cavity (which has yellow marrow in it).

Question 22

What is the epiphysis and what is it made of?

Answer 22

Epiphysis is the bulbous endings of long bones. This region of the bone is composed of trabecular bone that contains red marrow. Each epiphysis is surrounded by articular cartilage

Question 23

What is another name for red blood cells? White blood cells?

Answer 23

Red blood cells - erythrocytes

White blood cells - leukocytes

Question 24

What is articular cartilage?

Answer 24

A protective layer the covers the epiphysis of a bone.

Question 25

What is an osteon?

Answer 25

a functional unit of a bone

Here is a picture of what all these functions look like:

Question 26

What is a haversian canal?

Answer 26

passage ways that travel length ways through the bone.

Here is a picture of what all these functions look like:

Question 27

How many haversian canals does each osteon connect to?

Answer 27

one

Question 28

Practically perpendicular to the haversian canals, what passage way interconnects with the haversian canals?

Answer 28

perforating or Volksman canals.

Here is a picture of what all these functions look like:

Question 29

What is a lacunae?

Answer 29

tiny cavities that are layed out in circles and provide homes for osteocytes.

Here is a picture of what all these functions look like:

Question 30

What are osteoblasts?

Answer 30

cells that build new bone tissue

Question 31

What are osteoclasts?

Answer 31

cells that eliminate weakened or damaged bone tissue

Question 32

What is bone modeling?

Answer 32

the process in which new bone is created through osteoblast activity during the formation and growth of immature bones

Question 33

The skeleton of early-developing embryos is mainly composed of what flexible tissue?

Answer 33

hyline cartilage

Question 34

the process of bone formation is called what?

Answer 34

ossification

Question 35

Where do bones grow in length?

Answer 35

at the epiphyseal plate

Question 36

How do bones grow in length?

Answer 36

osteoblasts produce new bone cells at the epiphyseal plate which produces bone length

Question 37

How do bones grow in circmference?

Answer 37

Osteoblasts add layers of bone on top of old layers and osteoclasts resorb layers inside the medullary cavity causing the cavity to enlarge.

Question 38

What is hypertrophy?

Answer 38

hypertrophy is the act the causes physically active people to have stronger, denser bones than sedentary people

Question 39

How much of a person’s body weight do bones account for?

Answer 39

about 15% regardless of body weight

Question 40

What is atrophy?

Answer 40

Atrophy is the opposite of hypertrophy, and causes less active people to have weaker bones.

Question 41

About how many bones does an infant have? Why?

Answer 41

an infant has about 300 bones because many of the single bones that adults have were 2 bones that fused together as the infant got older.

Question 42

What three main parts is the axial skeleton composed of?

Answer 42

the skull, the verebral column, and the thoracic cage

Question 43

What is a suture?

Answer 43

sutures are immovable joints

Question 44

Fonatelle

Answer 44

baby soft spots in the skull

Question 45

What two functions do fonatelles serve?

Answer 45

1. they allow compression of the skull during birth
2. they allow brain growth pre- and post- birth

Question 46

How many vertebrae comprise the spine?

Answer 46

33

Question 47

How are the cervical, thoracic, and lumber vertebrae different?

Answer 47