Supporting Tissue

Question 1

Hyaline cartilage

Answer 1

• main components: extra cellular ground substance and collagenous fibers
• smooth and evenly placed
• contains no nerves nor blood vessels
• gets nutrients/oxygen though movement
• buried in the matrix are the lacunae cavities containing the chrondrocytes

Question 2

Lacunae

Answer 2

• cavities containing the chrondrocytes (cells of the cartilage)

Question 3

Capsule

Answer 3

• not a discrete structure, but is present in stained slides

Question 4

Perichondrium

Answer 4

• connective tissue around the cartilage
• the cells of its innermost layer look like ordinary fibroblasts, but are actually primitive cartilage cells

Question 5

Elastic cartilage

Answer 5

• numerous fibers of elastin that are very visible
• less matrix and more indigenous groups of chrondrocytes
• “dirty” and packed (when stained w/ orecin)

Question 6

Fibrocartilage

Answer 6

• fare/difficult to find
• visible bands of eosinophilic collagen
• dense regular CT
• the cells in their lacunae tend to line up btwn the eosinophilic bands of collagen, but are similar to hyaline cartilage

Question 7

Tendon

Answer 7

• very symmetrical arrangement of fibers and nuclei
• no lacuna, no nerves, look for “railroads”
• contains fibroblasts

Question 8

Bone

Answer 8

• its ground substance is impregnated with a hydrated calcium phosphate salt called hydroxyapatite
• 2 categories: cancellous (spongy bone) and compact bone

Question 9

Cancellous (spongy) bone

Answer 9

• ## has spicules (thin walls) of bone amidst many cells

Question 10

Compact bone

Answer 10

• outer bone is called compact bone, while the inner marrow cavity may be cross-crossed by thin strands of bone called trabeculae
• all mature bone is formed in layers called lamellae which are organized into sets of concentric rings called osetons or Haversian
• within the lamellae are small spaces (lacunae) in which osetocytes reside
• naeighboring lacunae are interconnected by thin channels (canaliculi)

Question 11

Ground bone

Answer 11

• desiccated (or dried up) bone that is ground so thin as to be translucent (not stained)
• calcium
• Haversian canal is the inside part of a osteon
• canaliculi are the thin lines in the osteon
• osteocyte lacunae is the black dots in the osteon

Question 12

Red marrow

Answer 12

• most of the bone in the skull surrounds red marrow
• the combo of 2 compact bony plates sandwiching a layer of cancellous bone and its as associated red marrow is called diploe

Question 13

Yellow marrow

Answer 13

• found inside the shafts of adult long bones
• contains white fat addition to the hemopoetic tissue

Question 14

Osteoclasts

Answer 14

• resorption bay (reabsorbs the bone)
• “clash of the titans”

Question 15

Osteoblasts

Answer 15

• builds the layers of bone
• they increase the diameter of the bone by adding layers to its outside

Question 16

Osteocytes

Answer 16

• lives in lacuna

Question 17

Lamellae

Answer 17

• bone is laid down in layers called this
• the bone is then further organized into Haversian systems or osteons

Question 18

Volkman’s canals

Answer 18

• connections appear as canals and they carry blood vessels and verses laterally through the bone to the osteons

Question 19

Endosteum

Answer 19

• the layer of tissue that lines the inside of the bone (marrow cavity)

Question 20

Crown

Answer 20

• the region of the tooth above the gum line
• end of the tooth that has a tan colored

Question 21

Enamel

Answer 21

• the tan layer in the crown is this
• hardest substance that the body makes

Question 22

Dentin-enamel junction

Answer 22

• base of the enamel layer

Question 23

Dentin

Answer 23

• beneath the DEJ and is comprised most of the bulk of the tooth
• are oriented perpendicular to the surface of the tooth

Question 24

Dentinal tubules

Answer 24

• look like black lines which are roughly S-shaped
• look like whale teeth
• long, branching canals which bridge the entire width of the dentin

Question 25

Pulp cavity

Answer 25

• center of the tooth contains this cavity
• contains blood vessels, nerve fibers and lose CT collectively called pulp

Question 26

Cementum

Answer 26

• where the enamel ends the dentin is covered by cementum
• it is continuous over the remainder of the tooth, the roots
• the interface between the cementum and dentin is the cementum-dentin junction

Question 27

Apical foramen

Answer 27

• blood capillaries and nerves enter the pulp cavity though an apical foramen at the tip of each root

Question 28

Root canal

Answer 28

• dentin surround the both the pulp cavity and its extension into the root of the tooth as the root canal
• filled with fine CT, fibroblasts, histocytes, and dentin-forming cells

Question 29

Decalcified sections

Answer 29

• not the same as ground section