5 Written Questions

1. Glycoprotein in cartilage responsible for binding calcium to the ECM
2. - CTs that make up the skeletal framework of the body
   - consists of cartilage and bone
   - highly specialized
   - provide support for other soft tissues
3. Similar to hyaline cartilage (large, round widely scattered chondrocytes); contains randomly oriented elastic fibers and collagen II (secreted by chondrocytes); tolerates repeated bending better (external ear and the epiglottis)
4. Dense irregular connective tissue membrane covering cartilage
5. The amorphous gel rich in proteoglycans (keeps the wandering cells out); bluish color results from acidic nature of sulfur groups; contains a territorial matrix and an interterritorial matrix

5 Matching Questions

1. appositional growth
2. Development of cartilage
3. Hyaline Cartilage Functions
4. Aggrecan
5. Proteoglycan aggregates

1. a Cartilage forming cells from perichondrium secrete new matrix against the external face of existing cartilage; Growth from the outside
2. b 1. Mesenchyme (low O2 region) chondroblast cells condense → procartilage
   2. Procartilage secretes cartilage matrix (interstitial growth)
3. c hyaluronic acid molecule w/ 100 aggrecan molecules attached which give the ground substance a gel-like character; Functions: diffuse nutrients, resist compression and be slippery (mother nature's teflon)
4. d predominant proteoglycan subunit, core protein w/ condroitin-4/6-suflate & keratan sulfate attached; bottle brush appearance
5. e structural support; withstand pressure and shear forces; slippery; capable of rapid growth

5 Multiple Choice Questions

1. Chondrocyte (large, round and widely scattered) is principal fixed cell type; strong, densely packed collagen I fibers with little ground substance (looks like dense regular CT); in structures needing to withstand tension and pressure (pubic symphysis, intervertebral discs, junction at attachment btw. tendon and bone)
   1. Cartilage
   2. Fibrocartilage
   3. Fibrous layer
   4. Hyaline Cartilage
2. aka cell nest, where two or more cells are in a single lacuna or closely associated w/ each other; site where chondroblast has recently undergone cell division & begun to lay down new matrix; example of interstitial growth
   1. Isogenous group
   2. Proteoglycans
   3. Fibrous layer
   4. Perichondrium
3. costal cartilage, trachea and bronchi of lungs, larynx and nasal cartilage, articular cartilage of synovial joints, fetal skeleton
   1. Fibrocartilage
   2. Hyaline Cartilage
   3. Location of Hyaline Cartilage
   4. Elastic cartilage
4. inner layer where cells of fibrous layer differentiate into chondroblasts and begin secreting ECM; appositional growth
   1. Chondronectin
   2. Perichondrium
   3. Chondrocalcin
   4. Chondrogenic layer (of perichondium)
5. most prevalent; contains large round cells (chondrocytes) separated by a large amt. of ECM (pale blue, amorphous, can't see fibers); avascular matrix; surrounded by layer of perichondrium (dense irregular CT)
   1. Elastic cartilage
   2. Fibrocartilage
   3. Hyaline Cartilage
   4. Cartilage

5 True/False Questions

1. interstitial growth → Chondrocytes divide and secrete new matrix to expand the cartilage from within; Growth from the inside; evidenced by isogenous groups

   True        False

2. Proteoglycans → give matrix its characteristic structure; important for cartilage function; organization of proteoglycans in matrix is more organized than in CT proper

   True        False

3. Lacunae → small spaces between the lamellae which contain osteocytes

   True        False

4. Chondroblast → cartilage fixed cell; 2+ cells in a single lacunae; secretes and lays down new additional ECM; capable of cell division; difficult to distinguish; have well-developed Golgi and rER characteristic of protein-secreting cells

   True        False

5. Pericellular capsule → CANNOT SEE at LM level; forms meshwork of collagen (type 2) immediately adjacent to the lacuna; works in protecting cells from mechanical stresses

   True        False