Skeletal System

Question 1

What are the primary functions of the skeletal system?

Answer 1

Support and protection
Lever system allowing movement
Blood cell production (bone marrow) red blood cells and platelets.
Mineral storage (primarily calcium and phosphorus in the bones)

Question 2

Spongy bone

Answer 2

Contains red marrow

Question 3

Epiphyseal plate

Answer 3

End of the bone with 3 different positions. Spongy bones at the end vs compact bones in the middle surrounding the spongy bones.

Question 4

Endosteum

Answer 4

Tissue layer inside the bone, lining the cavity

Question 5

Osteon

Answer 5

Long cylinder made of lamellae. Structural unit of compact bones

Question 6

Central canal (haversian)

Answer 6

Connects each canal to another.
-hollow venter of an osteon
-where blood vessels, lymphatic vessels and nerve run

Question 7

Trabecular

Answer 7

Sponge specs found in the bone. Little structures making up the spongy bone

Question 8

Medullary cavity

Answer 8

Single cell layer called endosteum (inside layer)

Question 9

Fibrous layer

Answer 9

Dense irregular connective tissue

Question 10

Osteoclasts

Answer 10

Help maintain compact bones. Within the connective tissue layer you will find blood vessels and nerves as well. Membrane sheath coating the entire bone.

Question 11

Hyaline cartilage

Answer 11

Clearer looking ground substance is the protective layer on the bone. Think joints where you will find synovial joints/elbow/knee/hip and the ribs, respiratory system, nose. Most prevalent and weakest

Question 12

Fibrocartilage

Answer 12

Densely layered collagen fibers. Strongest, high compressive strength. More flattened and organized cells rows. Ex. Menisci (knees) symphysis, intervertebral disks.

Question 13

Elastic cartilage

Answer 13

Visible elastic fibers in the matrix. Most flexible cartilage. Ex. Epiglottis (tissue protecting your airways from blood flying in. It’s like a little flap (ear, larynx-respiratory)

Question 14

Osteocytes

Answer 14

Blue cells that maintain bone tissue in the area

Question 15

Osteoblasts

Answer 15

B for building and maintaining function of the bone. One completely surrounded by bone matrix, becomes osteocytes

Question 16

Osteoclasts

Answer 16

(Catastrophe) breaks down the bone.

Question 17

What do connecting both canals do?

Answer 17

Allows more efficient transport through the bone tissue.

Question 18

Lacunae

Answer 18

Osteocytes in the bone tissue that divot within bone matrix where the bone cells sit in. Little cavity that houses the cells.

Question 19

Canaliculi

Answer 19

Connects adjacent lacunae

Question 20

How big is an osteon?

Answer 20

200um a long bone with 2-3 inches (necessary to visualize) bone cells and micro structures

Question 21

Lamellae

Answer 21

Cylindrical tubes that make up the osteon

Question 22

Perforating

Answer 22

Connects adjacent central canals

Question 23

In the bone matrix, what organic components are based in the osteoid?

Answer 23

-1/3 of the matrix
-ground substance (proteoglycans) and collagen fibers
-secrets by osteoblasts
-give bone tensile strength (stretching or pulling)

Question 24

What are the inorganic components of the bone matrix? (The minerals salts)

Answer 24

-account for remaining 2/3
-mostly calcium phosphates (fairly inflexible and more prone to breaking
-give bone compressive strength

Question 25

Tensile strength

Answer 25

Is stretching down

Question 26

Compressive strength

Answer 26

The osteoclasts (up)

Question 27

Wolff’s law

Answer 27

Bone will adapt to the loads that are placed one it. When bones have stress they will adapt to it. Usually a bump on the fracture made of a bunch tissues after a breakage in the bone. Body’s way of preventing it from happening again