Week 4

Question 1

Is bone called “osseous tissue”

Answer 1

Yes

Question 2

What type of tissue is bone

Answer 2

Hard, dense connective tissue

Question 3

What are the 5 functions of the skeletal system?

Answer 3

1) support the body
2) facilitate movement - don’t actually move the body, but attach to muscles which do move the body
3) protect internal organs
4) produce blood cells
5) storage depot for minerals and fat

Question 4

What is yellow marrow made up of

Answer 4

Fat storage

Question 5

What process happens in red marrow?

Answer 5

Hematopoiesis (blood cell production: RBC’s, WBC’s, platelets)

Question 6

What are the 5 types of bone?

Answer 6

1) long bones
2) short bones
3) flat bones
4) irregular bones
5) sesamoid

Question 7

What do long bones look like and what is their function? Give an example.

Answer 7

Cylinder shaped, longer than wide. Provides attachment for movement. Example: femur (in leg)

Question 8

What do short bones look like and what is their function?

Answer 8

They are cube shaped. They provide stability and support for fine motor movements.

Question 9

What are the 2 only locations short bones are found, and what are they called in each place?

Answer 9

Carpals - wrist bones
Tarsals - ankle bones

Question 10

What do flat bones look like and what is their function? Give an example.

Answer 10

They are thin and curved. They provide points of attachment for muscles and protect internal organs. Example: ribs, skull

Question 11

What do irregular bones look like and what is their function? Give an example.

Answer 11

They have a complex shape. Protect internal organs. Vertebrae

Question 12

What do sesamoid bones look like and where are they found? What is their function?

Answer 12

They are small and round (shaped like a sesame seed). They form in tendons where there is pressure. They protect tendons from compressive forces.
(*tendons attach muscle to bone)

Question 13

Where are sesamoid bones found in the body? Give an example.

Answer 13

Found in tendons in feet, hands and knees. An example is the patella, which is in front of the knee cap.

Question 14

What are the 2 parts of the long bone?

Answer 14

Diaphysis (shaft)
Epiphysis (end)

Question 15

What does the medullary cavity consist of in the long bone? What does the spongy bone consist of?

Answer 15

The medullary cavity - yellow marrow
Spongy bone - red marrow

Question 16

What is the epiphyseal plate in long bones? When does it stop growing and what happens to it then?

Answer 16

It is the growth plate that allows bone to grow in length. It stops growing at 18-21 years of age, where it then becomes the epiphyseal line.

Question 17

What is the endosteum in long bones?

Answer 17

It is the membrane that lines the inner cavity of the diaphysis.

Question 18

What is the periosteum in long bones? What does it contain and what is its function?

Answer 18

It covers the outer surface of bones. It contains blood vessels, nerves, and lymphatic vessels.
It attaches tendons and ligaments to bone.

Question 19

What covers the ends of bone that articulate (join) with others?

Answer 19

Articular cartilage

Question 20

What are the two things bone consists of? What are each one’s function

Answer 20

2/3 calcium - strength
1/3 collagen fibres - flexibility

Question 21

How does remodelling work for bones (= process of breaking down and building bone) - what process happens?

Answer 21

Negative feedback - stress is the stimulus (i.e. weight bearing through walking
No stress = less bone (becomes more thin)
More stress = more bone (becomes more thick)

Question 22

What are the 4 types of cells within bone tissues?

Answer 22

1) Osteoblasts
2) Osteocytes
3) Osteogenic cells
4) Osteoclasts

Question 23

What is the function of osteoblasts? Where are they located?

Answer 23

Form bone.
Found in growing portions of bone, including periosteum and endosteum.

Question 24

What is the function of osteocytes? Are they the primary cell of mature bone? Where are they located?

Answer 24

They are responsible for mineral balance in our body. Yes, they are.
They are stuck in the bone matrix.

Question 25

What is the function of osteogenic cells? Where are they located?

Answer 25

They are undifferentiated stem cells that develop into osteoblasts. They are found in deep layers of periosteum and the marrow.

Question 26

What is the function of osteoclasts? Where are they located?

Answer 26

They are responsible for bone resorption = breakdown of the bone and release its calcium to the blood. They are found in bone surfaces and at sites of old, injured or unneeded bone

Question 27

The balance of which two bone cells is responsible for the constant reshaping of bone?

Answer 27

The balance between osteoblasts and osteoclasts.

Question 28

Where is compact bone found?

Answer 28

It makes up the outer layer of the bone

Question 29

What is an osteon / haversian system in compact bone structure?

Answer 29

In compact bone structure, it is a haversian canal and the surrounding lamellae (rings of calcified bone) and lacunae (bone cavities / holes). *it is the basic structural unit of compact bone.

Question 30

What are perforating / volkmann’s canals? What is their function?

Answer 30

They are the channels found in the bone that transmits blood vessels from the periosteum into the bone and communicates with the haversian canals.

Question 31

What is lamellae?

Answer 31

Rings of calcified matrix

Question 32

What is lacunae?

Answer 32

Bone cavities holes

Question 33

What is spongy bone made of? What characterizes this material?

Answer 33

Trabeculae, which is light

Question 34

What happens to spongy bone when you put stress on it?

Answer 34

More trabeculae is made = thicker bone = healthier bone

Question 35

Where do arteries enter in bone?

Answer 35

Through nutrient foramina / foreman, which is an opening into the bone shaft

Question 36

From where do osteocytes get nourished in spongy bone?

Answer 36

1) From blood vessels of periosteum that penetrate through
2) by blood that passes through marrow cavities

Question 37

What are the 3 functions of nerve supply in the skeletal system?

Answer 37

1) sense pain
2) regulate blood flow
3) regulate bone growth

Question 38

What cells form cartilage and what do these cells become?

Answer 38

Cartilage comes from chondroblasts which become chondrocytes.

Question 39

What does bone use to build tissue?

Answer 39

Cartilage - bone forms from cartilaginous matrix

Question 40

What is the epiphyseal plate - what happens here? Was it made of?

Answer 40

It’s made up of cartilage.
It is the area of growth in long bone. It is where ossification occurs in immature bone.
(the new bone matrix pushes epiphysis away from diaphysis)

Question 41

What is the epiphyseal line?

Answer 41

It is an epiphyseal plate that has become ossified (= turned into bone) in mature bone

Question 42

What does appositional growth mean?

Answer 42

Bones growing in diameter (can continue to happen even after they stop growing in length) due to stress

Question 43

What two cells are in charge of appositional growth?

Answer 43

1) osteoclasts = resorb old bone (break them down)
2) osteoblasts = produce new bone beneath periosteum
This increases diameter of the bone

Question 44

Why is calcium needed for bones?

Answer 44

To make calcium phosphate and calcium carbonate, which form what gives bone its hardness

Question 45

Why is vitamin D needed for bones? What is the one source of it?

Answer 45

Needed for calcium absorption. Sunlight.

Question 46

Why is vitamin K needed for bones

Answer 46

It supports bone mineralization

Question 47

Why is magnesium needed for bones?

Answer 47

It is the structural component of bones