the skeletal system

Question 1

define: skeletal system

Answer 1

network/ framework of bones working in conjunction with muscles, cartilage, tendons, and ligaments, to perform various functions

Question 2

what are some functions of the skeletal system?

Answer 2

• provides structure/ form
• protects vital internal organs
• provides sites for muscle attachment, allows for movement
• hematopoiesis (produces blood cells)
• storage reservoir for minerals

Question 3

define: hematopoiesis

Answer 3

production of blood cells

Question 4

define: osteology

Answer 4

the study of bones

Question 5

what are the different classifications of bones?

Answer 5

1. long bone
2. short bone
3. sesamoid bone
4. flat bones
5. irregular bones

Question 6

what are the characteristics of a long-bone

Answer 6

1. longer than they are wide
2. are the main supporting bones
3. diaphysis, 2 epiphysis, and a marrow cavity
   e.g., humerus, femur, radius, tibia

Question 7

what are the characteristics of a short bone?

Answer 7

1. are as long as they are wide (cube-like)
2. small
3. has a thin layer of hard compact bone with a softer spongy bone between the layers
   e.g., tarsals, carpals

Question 8

what are the characteristics of flat bones?

Answer 8

1. broad surface area
2. thin and flat
3. two layers of compact bone with a spongy bone between the layers
4. no central marrow cavity
5. have a protective function
6. some contain air-filled spaces
   e.g., scapula, pelvis, ribs, many bones of the skull

Question 9

what are the characteristics of sesamoid bones?

Answer 9

1. sesame seed shaped
2. small and short
3. attached (embedded in) to tendons
4. is in areas where a change in the direction of pull of a tendon or ligament is required (reduce friction along a joint)
   e.g., patella, fabellae

Question 10

what are the characteristics of irregular bones?

Answer 10

1. bones that don’t fit into any other category
2. unpaired bones (b/c their shapes are more complex)
3. misc.
   e.g., vertebrae, some skull bones

Question 11

what are the different structures of the long bone?

Answer 11

1. epiphysis
2. diaphysis
3. periosteum
4. medullary cavity
5. endosteum
6. cortical bone
7. cancellous bone
8. articular surface
9. epiphyseal plate (growth plate)

Question 12

epiphysis

Answer 12

the proximal and distal ENDS of the long bone

Question 13

diaphysis

Answer 13

• shaft of the long bone
• hollow

Question 14

periosteum

Answer 14

• thin but tough living connective tissue layer (like living saran wrap)
• covers the external/outside surface of the long bone except where the articular cartilage is found
• rich in blood, nerves, and lymphatic vessels
• tightly adhered

Question 15

medullary cavity

Answer 15

• the inner center of the long bone
• aka marrow cavity
• contains blood-forming tissue (red bone marrow)
• yellow bone marrow

Question 16

red bone marrow

Answer 16

• in the medullary cavity of any animal still growing, then recedes to the epiphysis
• Blood-forming tissue
• fills the marrow cavity in newborns

Question 17

yellow bone marrow

Answer 17

• fatty tissue
• common in adult animals
• can revert to red bone marrow to create RBC but this takes time