Topic 9 - SKELETAL SYSTEM

Question 1

skeletal system overview:

functions:

1. support
2. ?
3. attaches muscles + allows movement
4. ?
5. stores Ca⁺⁺

Answer 1

1. support
2. protection of vital organs
3. attaches muscles + allows movement
4. red marrow produces rbc, wbc
5. stores Ca⁺⁺

Question 2

skeletal system overview:

functions

1. ?
2. protection of vital organs
3. ?
4. red marrow produces rbc, wbc
5. ?

Answer 2

1. support
2. protection of vital organs
3. attaches muscles + allows movement
4. red marrow produces rbc, wbc
5. stores Ca++

Question 3

skeletal system overview

what are the 5 functions?

no hints

Answer 3

1. support
2. protection of vital organs
3. attaches muscles + allows movement
4. red marrow produces rbc, wbc
5. stores Ca++

Question 4

Bone Ossification:

1

before week 8, skeleton of _______ constructed of ________ membranes + _________ cartilage

Answer 4

before week 8, skeleton of embryo constructed of fibrous membranes + hyaline cartilage

Question 5

bone ossification:

1

before _____ _, ________ of embryo ________ of fibrous _______ + hyaline _______

Answer 5

before week 8, skeleton of embryo constructed of fibrous membranes + hyaline cartilage

Question 6

bone ossification:

1

what happens before week 8?

Answer 6

before week 8, skeleton of embryo constructed of fibrous membranes + hyaline cartilage

Question 7

bone ossification

when does bone formation begin and end?

Answer 7

8th week ⇒ 20 years

Question 8

what are the 2 types of bone ossification?

Answer 8

1. intramembranous ossification
2. endochondral ossification (most bones)

Question 9

Intramembranous ossification

1. ___ bones (e.g. ____ ____ ____, mandible, ______
2. _______ from fibrous CT membrane
3. process:

• osteoblasts ________ spongy bone along __ ______
• periosteum _____ and then ________ under it ___ _____ compact bone

1. _______ = unossified membranes __ ___ ____ that remain at birth

Answer 9

Intramembranous ossification

1. flat bones (e.g. some skull bones, mandible, clavicle
2. develop from fibrous CT membrane
3. process:
   
   • osteoblasts produce spongy bone along CT fibres
   • periosteum forms and then osteoblasts under it lay down compact bone
4. fontanels = unossified membranes in the skull that remain at birth

Question 10

Intramembranous ossification

• flat ____ (e.g. some skull bones, ________, clavicle
• develop from ______ ___ _______
• process:
  
  • _______ produce ____ _____ along CT fibres
  • ______ forms and then osteoblasts ____ __ lay down ______ _____
• fontanels = _______ _______ in the skull that ______ __ _____

Answer 10

Intramembranous ossification

• flat bones (e.g. some skull bones, mandible, clavicle
• develop from fibrous CT membrane
• process:
  
  • osteoblasts produce spongy bone along CT fibres
  • periosteum forms and then osteoblasts under it lay down compact bone
• fontanels = unossified membranes in the skull that remain at birth

Question 11

intramembranous ossification

no hints

4 points

Answer 11

Intramembranous ossification

1. flat bones (e.g. some skull bones, mandible, clavicle
2. develop from fibrous CT membrane
3. process:
   
   • osteoblasts produce spongy bone along CT fibres
   • periosteum forms and then osteoblasts under it lay down compact bone
4. fontanels = unossified membranes in the skull that remain at birth

Question 12

endochondral ossification (most bones)

1. _______ ______ as a model (____ _____) for bone construction - then _____ to form _____ _____
2. _________ forms and the ________ ______ lay down _______ ______
3. articular cartilage + ______ _____ = ______ ____ ____ ____ ______

Answer 12

1. hyaline cartilage as a model (similar shape) for bone construction - then ossifies to form spongy bone
2. periosteum forms and the osteoblasts beneath lay down compact bone
3. articular cartilage + epihyseal plates = cartilage that has not ossified

Question 13

1. hyaline cartilage __ _ _____ (similar shape) for ____ _________ - then ossifies __ _____ spongy bone
2. periosteum _____ and the osteoblasts beneath ___ ______ compact bone
3. _______ _____ + epihyseal plates = cartilage that has not _______

Answer 13

1. hyaline cartilage as a model (similar shape) for bone construction - then ossifies to form spongy bone
2. periosteum forms and the osteoblasts beneath lay down compact bone
3. articular cartilage + epihyseal plates = cartilage that has not ossified

Question 14

endochondral ossification

no hints (3 points)

Answer 14

• hyaline cartilage as a model (similar shape) for bone construction - then ossifies to form spongy bone
• periosteum forms and the osteoblsts beneath lay down compact bone
• articular cartilage + epihyseal plates = carilage that has not ossified

Question 15

bone growth (postnatal)

Growth in Length

= __________ growth - at ?

Answer 15

= endochondral growth - at epiphyseal plates

Question 16

bone growth (postnatal)

Growth in Length

process

• cartilage ______ ⇒ matrix near _______ becomes ______
• _______ __ ______ stops when _______ ____ ossifies into ________ ______ (closure)

Answer 16

• cartilage grows ⇒ matrix near diaphysis becomes bone
• growth in length stops when epiphyseal plate ossifies into epiphyseal line (closure)

Question 17

bone growth (postnatal)

Growth in Length

process

1. ______ grows ⇒______ near diaphysis _______ bone
2. growth in length _____ when epiphyseal plate ______ into epiphyseal line (______)

Answer 17

1. cartilage grows ⇒ matrix near diaphysis becomes bone
2. growth in length stops when epiphyseal plate ossifies into epiphyseal line (closure)

Question 18

bone growth (postnatal)

Growth in Length

process

no hints (2 points)

Answer 18

1. cartilage grows ⇒ matrix near diaphysis becomes bone
2. growth in length stops when epiphyseal plate ossifies into epiphyseal line (closure)

Question 19

Bone Growth (postnatal):

Growth in Diameter

= _________ growth

Answer 19

appositional growth

Question 20

bone growth (postnatal):

growth in diameter

process:

1. _______ beneath ________ secrete ______ _______ (External bone surface)
2. _________ resorb ____ on the ________ _____. Therefore, _____ __ ______ keeps pace with _______ ____

Answer 20

1. osteoblasts beneath periosteum secrete bone matrix (External bone surface)
2. osteoclasts resorb bone on the endosteal surface. Therefore, size of cavity keeps pace with growing bone

Question 21

bone growth (postnatal):

growth in diameter

process:

1. osteoblasts ________ periosteum _______ bone matrix (_______ ______ ______)
2. osteoclasts _____ bone ___ ___ endosteal surface. Therefore, size of cavity ____ _____ _____ growing bone

Answer 21

1. osteoblasts beneath periosteum secrete bone matrix (External bone surface)
2. osteoclasts resorb bone on the endosteal surface. Therefore, size of cavity keeps pace with growing bone

Question 22

bone growth (postnatal):

growth in diameter

process:

no hints (2 points)

Answer 22

1. osteoblasts beneath periosteum secrete bone matrix (External bone surface)
2. osteoclasts resorb bone on the endosteal surface. Therefore, size of cavity keeps pace with growing bone