Skeletal System Vocab/Notes

Question 1

What are the main functions of the skeletal system? (5)

Answer 1

• support (framework)
• protection
• movement
• storage (minerals, especially calcium + phosphorous)
• blood cell production

Question 2

Hematoporesis

Answer 2

Blood cell production

Question 3

What minerals does the skeletal system mainly produce? (2)

Answer 3

• calcium
• phosphorous

Question 4

What are the components of the skeletal system (5)

Answer 4

• bones
• cartilage
• tendons
• ligaments
• marrow

Question 5

What types of tissues are found in the skeletal system? (3)

Answer 5

• nervous
• cartilage
• fibrous connective tissue

Question 6

What tissues are found in the blood vessels?

Answer 6

• epithelial cells
• muscle cells

Question 7

What cells are present in bone? (4)

Answer 7

• osteogenic
• osteoblasts
• osteocytes
• osteoclasts

Question 8

Osteogenic cell function + location

Answer 8

• develop into osteoblasts/stem cells
• deep in periosteum marrow

Question 9

Osteoblast cell function + location

Answer 9

• bone formation
• growing parts of bone (Periosteum + endosteum)

Question 10

Osteocyte cell function + location

Answer 10

• maintain bone tissue
• in matrix

Question 11

Osteoclast cell function + location

Answer 11

• resorbs bone
• bone surfaces

Question 12

The bone matrix is made out of … and … substances

Answer 12

Organic … Inorganic

Question 13

Organic substance in bone matrix

Answer 13

Collagen

Question 14

What does collagen do/what is it made up of?

Answer 14

Provides flexible strength
Made out of Proteoglycans

Question 15

Inorganic substance in bone matrix

Answer 15

Hydroxyapetite (Calcium phosphate salt)

Question 16

What does hydroxyapetite do/what is it made up of?

Answer 16

It provides weight bearing strength
Made out of minerals

Question 17

Osteons

Answer 17

Structural unit of bones

Question 18

Parts of osteons (4)

Answer 18

• lacunae
• lamellae
• haversian canal
• canaliculi

Question 19

Vascular supply parts of bone (3)

Answer 19

• Haversian canal
• Volkmann’s canals
• Canaliculi

Question 20

Haversian Canal function

Answer 20

Central canal that supply the osteons w blood

Question 21

What does the haversian canal contain (3)

Answer 21

Blood vessels
Nerves
Lymphatic vessels

Question 22

Volkmann’s canals

Answer 22

move blood between osteons

Question 23

Canaliculi

Answer 23

Small channels connecting lacunae that allow nutrients + waste to move

Question 24

Parts of a long bone (9) (recommend labelling them)

Answer 24

• diaphysis
• epiphysis
• growth plate
• articular cartilage
• medullary canal
• periosteum
• endosteum
• spongy bone
• compact bone

Question 25

Structure of flate bone (3)

Answer 25

- periosteum - compact bone - spongy bone

Question 26

Spongy bone contains ...

Answer 26

Trabeculae

Question 27

Characteristics of trabeculae (4)

Answer 27

- helps resist stress - no osteons - irregularly arranged lanellae + osteocytes - capillaries in endosteum supply nutrients

Question 28

What is ossification?

Answer 28

Process of bone formation

Question 29

What are the two types of ossification?

Answer 29

Intramembranous Endochondral

Question 30

Intramembranous ossification occurs in...

Answer 30

The flat bones of the skull (think newborns)

Question 31

Endochondral ossification occurs in ...

Answer 31

The growth plate of long bone

Question 32

Steps to intramembraneous ossification (3)

Answer 32

1. osteogenic cells from bones move to collagen fibers between 2. osteogenic cells -> larger osteoblasts (produce calcium phosphate) that construct trabeculae, filling space with spongy bone 3. osteoblasts create bone osteons around spongy bone, sealing it in

Question 33

Steps to endochondral ossification (you got this!) (5)

Answer 33

1. growth hormone released, stimulates chondrocytes to rapidly divide (lengthens bone by increasing growth plate) 2. More chondrocytes = less nutrients, outer chondrocytes get bigger + expand bone length (but boom they die) 3. osteogenic cells replace dead chondrocytes (RIP), put down collagen as support 4. osteogenic cells -> osteoblasts, create trabeculae/spongy bone 5. osteoblasts add compact bone osteons on outside, sealing it in

Question 34

Trabeculae is ...

Answer 34

a unit of spongy bone

Question 35

Appositional growth =

Answer 35

increase in bone thickness

Question 36

Growth hormone (2)

Answer 36

- triggers rapid chondrocyte increase in epiphyseal plates (increases bone length - increases calcium retention

Question 37

Thyroxine (hormone produced by thyroid gland)

Answer 37

- promotes osteoblast activity + synthesis of bone matrix

Question 38

Testosterone + estrogen (3)

Answer 38

- promotes osteoblastic acivity + bone matrix production - responsible for growth spurt - end growth by inducing epiphyseal plate closure

Question 39

Why is calcium necessary for bone growth?

Answer 39

Needed to make calcium phosphate + calcium carbonate, which form hydroxyapatite (gives bone hardness)

Question 40

Why is vitamin D necessary for bone growth?

Answer 40

Needed for calcium absorption