Marieb Human Anatomy & Physiology - Chapter 06: Bones and Skeletal Tissues

These flashcards cover key concepts and details from Chapter 06 of Marieb's Human Anatomy & Physiology regarding bones and skeletal tissues.

What are the three types of cartilage and their primary features?

1. Hyaline cartilage - provides support, flexibility, and resilience; most abundant, contains only collagen fibers. 2. Elastic cartilage - similar to hyaline, but contains both collagen and elastic fibers; found in external ear and epiglottis. 3. Fibrocartilage - thick collagen fibers for tensile strength; found in menisci of knee, pubic symphysis, and intervertebral discs.

What are the seven important functions of bones?

1. Support for body and soft organs. 2. Protection of brain, spinal cord, and vital organs. 3. Anchorage as levers for muscle action. 4. Mineral storage (calcium and phosphorus). 5. Blood cell formation (hematopoiesis). 6. Triglyceride storage for energy. 7. Hormone production (osteocalcin regulates insulin and energy expenditure).

How are bones classified based on shape?

1. Long bones - longer than wide; ex. limb bones. 2. Short bones - cube-shaped; ex. wrist and ankle bones. 3. Flat bones - thin and slightly curved; ex. sternum and ribs. 4. Irregular bones - complicated shapes; ex. vertebrae.

What are the characteristics of compact bone?

Compact bone is a dense outer layer, appears smooth and solid, and consists of tightly packed osteons (Haversian systems) that provide structural support.

What is the process of intramembranous ossification?

Intramembranous ossification begins with mesenchymal cells clustering to form ossification centers, followed by secretion and calcification of osteoid, forming woven bone, which is later replaced by lamellar bone.

What are the five main steps in endochondral ossification?

1. Bone collar forms around the diaphysis. 2. Central cartilage calcifies and develops cavities. 3. Periosteal bud invades cavities to form spongy bone. 4. Diaphysis elongates and medullary cavity forms. 5. Epiphyses ossify; hyaline cartilage remains in epiphyseal plates and articular cartilages.

What major tissue types are found in bone?

Bone contains osseous (bone) tissue, nervous tissue, cartilage, dense connective tissue, muscle cells, and epithelial cells in its blood vessels.

What role do osteoblasts play in bone development?

Osteoblasts are bone-forming cells that secrete unmineralized bone matrix called osteoid, which is composed of collagen and calcium-binding proteins.

Explain what occurs during bone remodeling.

Bone remodeling replaces 5-10% of bone annually, involving bone deposition by osteoblasts and bone resorption by osteoclasts to maintain bone strength and mineral balance.

What is osteoporosis, and what are its risk factors?

Osteoporosis is a disease where bone resorption exceeds bone deposit, leading to decreased bone mass; risk factors include age, postmenopausal status, insufficient exercise, poor diet, and genetics.