Chapter 6 Bones And Skeletal Assignment Part 1 9th Ed 1 1

Alexis Garcia
Chapter 6-Bones and Skeletal Tissue

For this assignment, please read the chapter and answer the questions below.
Please type your answers in red or blue color.
Please note that points may be deducted if answers are not submitted in these colors.

Type your answer in the spaces provided below:

Skeletal System:

Describe each of the following functions of the Skeletal System I. support- Provides framework that supports the body and cradles its soft organs. II. protection- The fused bones of the skull protect the brain. The vertebra surrounds the spinal cord and the rib cage protects vital organs of the thorax. III. Body movement- Skeletal muscles, which attach to the bones by tendons, use bones as levers to move the body and parts. IV. Blood cell formation- they occur in the red marrow cavities of certain bones. V. mineral storage- bone is a reservoir for minerals, most importantly calcium and phosphate. They are released into the blood stream in ionic form as needed to all parts of the body.

Long Bone Structure:

The ends of bones that form joints with adjacent bones are called the _ epiphyses _.

The ends of these bones are covered with _epiphyseal plate_ (hyaline cartilage).

The epiphyseal plate is the site of bone _bone growth__.

The shaft of the bone is called the _diaphysis_.

The diaphysis contains a hollow chamber called the __medullary__ cavity that is lined with

_endosteum__ and filled with _marrow_.

Bone Marrow – Two Types:

What is the function of red marrow? It’s to generate blood cells

Where is it found? It’s found within the trabecular cavities of spongy bone of long bones and in the diploe of flat bones. What is the function of yellow marrow? It can revert red marrow if a person becomes anemic and needs more red blood cells. Where is it found? It’s found in the medullary cavity.

A tough layer of vascular connective tissue, called the __periosteum__, covers the bone and is continuous with ligaments and tendons.

Bone cells – There are 4 types of bone tissue cells. Describe their function in living bone tissue.

a. Osteogenic cells – mitotically active stem cells found in the membranous periosteum and endosteum. b. Osteoblasts – bone forming cells that secrete the bone mixture. c. Osteocytes – monitor and maintain the bone mixture. d. Osteoclasts – when actively resorbing bone, it rests in a shallow depression called resorption bay.
Microscopic Structure: The Osteon

Bone cells called _osteocytes__ are located within spaces called _lacunae_ that lie in concentric circles around _osteonic__ canals that contain blood vessels and nerves.

Osteocytes pass nutrients and wastes back and forth in grooves in the matrix called canaliculus__.

The intercellular material consists of collagen and inorganic calcium salts. Collagen makes the bone _soft__, while the calcium salts make the bone __hard_.

Bone Structure:

Describe spongy bone structure: it’s to provide support

Where is spongy bone found? It’s found inside the compact bone.

Describe compact bone: it looks like a poorly organized, even haphazard tissue.

In compact bone, osteocytes and intercellular material are organized into units called _osteaons_ that are cemented together.

Central canals contain blood vessels and nerve fibers, and extend in what direction through bone? Longitudinally Perforating canals connect the blood and nerve supply of the periosteum to what other structures? Medullary cavity Describe how the structure called a lamella forms compact bone. Compact bone forms a shell around cancellous bone and is the primary component of the long bones of the arm and leg and other bones Where is compact bone found? Outside spongy bone