Lab #3 (exercise 7-4)

What is the diaphysis?

The shaft of a long bone.

What is the epiphysis?

The end of a long bone.

What are the two epiphyses of a long bone?

Proximal epiphysis and distal epiphysis.

What is the medullary cavity?

The hollow area inside the shaft of a long bone.

What is usually found in the medullary cavity of an adult long bone?

Yellow bone marrow.

What is articular cartilage?

Hyaline cartilage covering the ends of the epiphyses where bones form joints.

What is the function of articular cartilage?

It allows bones at a joint to move with minimal friction.

What is the epiphyseal plate?

A band of hyaline cartilage where long bones grow in length.

What is another name for the epiphyseal plate?

Growth plate.

Where is the epiphyseal plate located?

Between the epiphysis and diaphysis.

What happens to the epiphyseal plate after growth in length stops?

It ossifies and becomes the epiphyseal line.

What is the epiphyseal line?

The remnant of the epiphyseal plate after it closes.

What is red bone marrow?

Bone marrow that produces blood cells.

What is yellow bone marrow?

Bone marrow composed primarily of adipose tissue.

What surrounds the medullary cavity in the diaphysis?

A thick collar of compact bone.

What type of bone is found inside the epiphyses?

Spongy bone surrounded by compact bone.

Where is articular cartilage located?

On the ends of the epiphyses.

What is the function of the epiphyseal plate?

Allows long bones to grow in length.

What happens in the zone of reserve cartilage?

It contains a reserve of chondrocytes that can divide if needed.

What happens in the zone of proliferation?

Chondrocytes actively divide.

What happens in the zone of hypertrophy and maturation?

Chondrocytes stop dividing, enlarge, and mature.

What happens in the zone of calcification?

Cartilage ECM accumulates calcium salt deposits and hardens as chondrocytes die.

What happens in the zone of ossification?

Osteoblasts lay down osteoid, resulting in newly formed bone.

What are the five zones of the epiphyseal plate in order?

Reserve cartilage, proliferation, hypertrophy and maturation, calcification, and ossification.

Which zone is closest to the epiphysis?

Zone of reserve cartilage.

Which zone contains actively dividing chondrocytes?

Zone of proliferation.

Which zone contains enlarged, maturing chondrocytes?

Zone of hypertrophy and maturation.

Which zone contains dying chondrocytes and calcified cartilage?

Zone of calcification.

Which zone is closest to the diaphysis?

Zone of ossification.

What happens when the epiphyseal plate closes?

The remaining cartilage ossifies and becomes the epiphyseal line.

What is the shaft of the long bone called?

Diaphysis.

What are the ends of the long bone called?

Epiphyses.

What is the hollow center of the shaft called?

Medullary cavity.

What type of marrow is generally in the adult medullary cavity?

Yellow bone marrow.

What type of marrow produces blood cells?

Red bone marrow.

What structure allows a long bone to grow in length?

Epiphyseal plate.

What structure is left after the epiphyseal plate closes?

Epiphyseal line.