cartilage and bone

Question 1

Q1: Can you observe elastic fibers in H&E preparations?

Answer 1

No, you need to use a dye specific for elastic fibers, e.g. orcein and fuchsin.

Question 2

Q2: What is a common feature of hyaline cartilage and elastic cartilage?

Answer 2

Elastic cartilage is similar to hyaline cartilage. Both have a perichondrium. Abundant elastic fibers provide increased flexibility to elastic cartilage.

Question 3

Q3: What are the common features of the above fibrocartilage preparations?

Answer 3

Fibrocartilage can be thought of as a hybrid tissue having characteristics of both dense connective tissue and hyaline cartilage. It is found where ligaments attach to cartilage (intervertebral disk, articular cartilage of bone, and ligament like tissue at the pubic sympysis) Note the absence of a perichondrium.

Question 4

Q4: What stains pink in the extracellular matrix of the bone?

Answer 4

Collagen fiber bundles.

Question 5

Q5: What is the relationship between Haversian and Volkmann’s canals?

Answer 5

Transverse or oblique Volkmann’s canals connect longitudinal Haversian canals. Both house blood and lymphatic vessels and nerves of the bone.

Question 6

Q6: What do the lacunae and canaliculi contain, respectively?

Answer 6

The cell body and long cytoplasmic processes of osteocytes.

Question 7

Q7: What is the relationship between osteoblasts and osteocytes?

Answer 7

Osteoblasts become osteocytes when they are completely surrounded by the extracellular matrix they produce.

Question 8

Q8: What are the histological characteristics of woven bone? Where do you find woven bone in the adult?

Answer 8

Very few osteons/Haversian systems are visible, osteocytes are larger, collagen bundles are arranged more haphazardly. Bone surrounding tooth root (allowing corrections with braces) in the maxilla and mandible, around sutures of the skull.