Skeletal System: Bone Tissues PPTX - q&a flashcards

What are the primary functions of the skeletal system?

Support, protection, levers for movement, hematopoiesis (blood cell production), and storage of minerals and energy reserves.

What are the two main divisions of the skeletal system?

Axial skeleton and appendicular skeleton.

How many bones are in the adult human skeleton?

Approximately 206 bones.

What type of cartilage is the most abundant in the body?

Hyaline cartilage.

What are the three types of cartilage?

Hyaline cartilage, elastic cartilage, and fibrocartilage.

What type of cartilage provides support and flexibility and is found in the external ear?

Elastic cartilage.

What is the role of the perichondrium?

It surrounds cartilage and contains blood vessels for nutrient delivery.

What are osteoblasts responsible for?

Producing the bony matrix and secreting osteoid.

What is hematopoiesis?

The production of blood cells, occurring inside bones.

What is the main difference between compact and spongy bone?

Compact bone is dense and smooth; spongy bone consists of a network of trabeculae with open spaces.

What structures cover the outer and inner surfaces of bones?

Periosteum covers the outside; endosteum covers the inside.

What is the function of osteoclasts?

To resorb or break down bone tissue.

What is the central medullary cavity filled with?

Red or yellow bone marrow.

What hormone is primarily responsible for stimulating bone growth in childhood?

Growth hormone.

What happens at the epiphyseal plate?

Cartilage is replaced by bone, allowing for lengthening of the bone.

What does the term 'ossification' refer to?

The process of bone connective tissue formation.

What are the two pathways of ossification?

Endochondral ossification and intramembranous ossification.

Which bones develop through endochondral ossification?

Most bones of the skeleton.

What is the importance of vitamin D in bone health?

It is required for the intestinal absorption of calcium.

What occurs during the calcification zone of the epiphyseal plate?

Cartilage matrix calcifies, causing chondrocytes to die.

What is the consequence of hypercalcemia?

High levels of calcium which can lead to nonresponsiveness and potential deposits of calcium salts.

What characterizes a compound fracture?

One or both ends of the broken bone pierce through the skin.

What are the four major stages of fracture healing?

Hematoma formation, fibrocartilaginous callus formation, bony callus formation, and bone remodeling.

What is the role of fibroblasts in fracture healing?

They secrete collagen fibers during fibrocartilaginous callus formation.

What type of bone marrow is involved in blood production?

Red bone marrow.

How does mechanical stress influence bone remodeling?

It signals osteocytes to increase the activity of osteoblasts, leading to thicker bones.

What happens to the epiphyseal plate after adolescence?

It thins and is replaced by bone, leading to cessation of bone lengthening.

What is the difference between nondisplaced and displaced fractures?

Nondisplaced fractures retain normal bone alignment; displaced fractures do not.

What is a stress fracture?

A thin break caused by increased physical activity.

How is compact bone structured?

It consists of osteons (Haversian systems) and contains concentric lamellae.

What is trabecular bone?

Bone formed by irregular lamellae and interconnected canaliculi, found in spongy bone.

What do osteocytes do?

Maintain the bone matrix and act as stress sensors.

What is the significance of the collagen fibers in bones?

They contribute to the tensile strength and flexibility of bone.

What do osteogenic cells differentiate into?

Osteoblasts or bone-lining cells.

What is the role of alkaline phosphatase in bone formation?

It adds mineral binding sites to collagen fibers.

How does blood supply enter bone?

Through nutrient foramina and the nutrient artery.

What type of bone forms the long shafts of bones?

Compact bone.

What are the characteristics of fibrocartilage?

Contains thick collagen fibers for great tensile strength to resist compression.

Which bones undergo intramembranous ossification?

Flat bones of the skull, mandible, and clavicle.

What is the purpose of the lamellae in compact bone?

They provide structural support and help resist twisting stress.

What happens during the growth plate closure?

The epiphyseal plate is replaced by bone, marking the end of growth in length.

What is the difference between complete and incomplete fractures?

Complete fractures break all the way through the bone; incomplete fractures do not.

What initiates the process of endochondral ossification?

The formation of a hyaline cartilage model.

What is the role of chondrocytes in bone growth?

They divide and secrete new matrix at the epiphyseal plate.

How do bones grow in width?

Through appositional growth where osteoblasts secrete bone matrix on the external surface.

What do osteoblasts secrete?

They secrete unmineralized bone matrix called osteoid.

What occurs during the ossification zone of the growth plate?

Chondrocytes deteriorate and columns of calcified cartilage are converted to bone.

What does the term 'diaphysis' refer to?

The shaft of a long bone.

What factors regulate bone remodeling?

Genetic factors and mechanical stress.

What happens during the process of bone resorption?

Bone matrix is destroyed by enzymes and acids released from osteoclasts.

What bones are primarily involved in hematopoiesis?

Bones of the axial skeleton.

What cells are considered bone-forming cells?

Osteoblasts.

What is an osteon?

The structural unit of compact bone.

What does the term 'calcification' mean in bone development?

The process by which collagen fibers are hardened with mineral deposits.

What are the two layers of the periosteum?

The fibrous layer and the osteogenic cellular layer.

What is the primary component of the bone matrix?

Osteoid, which consists mainly of collagen and proteins.

What structural features help connect osteocytes within the bone?

Canaliculi.

What does the term 'appositional growth' refer to?

The process where bones grow in width by adding new bone matrix.

How do hormones affect bone growth?

Hormones like growth hormone, thyroid hormone, and sex hormones influence bone deposition and resorption.

What is the primary role of osteoclasts during bone remodeling?

To break down old or damaged bone.

What major structure in the long bone contains blood vessels and nerves?

The central (Haversian) canal.

How does calcitonin function in bone health?

It inhibits osteoclast activity, lowering blood calcium levels.

What happens during the hematoma formation stage of fracture healing?

A mass of clotted blood forms at the fracture site, causing swelling and inflammation.

What occurs in the bony callus formation stage of fracture healing?

New trabeculae are formed in the fibrocartilaginous callus, creating spongy bone.

What type of connective tissue is found in the periosteum?

Dense irregular connective tissue.

What are the management strategies for a simple fracture?

Typically involve immobilization and pain management.

What is the function of the osteogenic layer of the periosteum?

It contains cells that contribute to bone growth and repair.

What marks the transition from childhood to adulthood in terms of bone growth?

The closure of the epiphyseal plate.

What factors can affect bone density?

Hormonal levels, physical activity, and nutritional state.

What is the relationship between mechanical stress and bone health?

Increased mechanical stress leads to bone strengthening and growth.

What are the histological layers involved in bone structure?

Lamellae, lacunae, and canaliculi.

What do the ruffled borders of osteoclasts increase?

Surface area for bone resorption.

What do trabeculae do in spongy bone?

They provide structural support and help bone resist stress.

What is the typical healing period for bone fractures?

Usually 2 to 3 months or longer, depending on the severity.

What is the impact of calcium and phosphate levels on bone health?

They are essential for mineralization and strength of bones.

How does the structure of short, irregular, and flat bones differ from long bones?

They consist of a thin layer of spongy bone covered by compact bone.

What is the main function of the axial skeleton?

To protect vital organs and provide support for the body.

What does the appendicular skeleton consist of?

Limbs and girdles that attach them to the axial skeleton.

What mineral is most important for bone hardness?

Calcium.

Which cells are responsible for bone repair?

Osteoblasts and osteoclasts.

What is the periosteum?

A dense layer of vascular connective tissue enveloping the bones.

How are compact and spongy bones different in composition?

Compact bone is dense and smooth; spongy bone is lighter and has a porous structure.

What are the primary functions of osteoclasts?

To break down bone tissue and regulate calcium levels.

What is the purpose of the endosteum?

To line the medullary cavity and regulate bone growth and repair.

What type of fracture occurs when the skin remains intact?

Closed or simple fracture.

What role do chondrocytes play in cartilage?

They produce and maintain the cartilaginous matrix.

What process describes the formation of bone from cartilage?

Endochondral ossification.

What is bone remodeling?

The ongoing replacement of old bone tissue by new bone tissue.

What happens during the fibrocartilaginous callus formation stage of fracture healing?

A soft callus forms, bridging the broken ends of the bone.

How does aging affect bone density?

Bone density decreases, leading to a higher risk of fractures.

What is the function of growth hormone in skeletal development?

Stimulates bone growth during childhood and adolescence.

What is an example of a long bone?

The femur.

What are osteogenic cells?

Stem cells that develop into osteoblasts.

What is the relationship between physical activity and bone density?

Increased physical activity promotes higher bone density.

What role does vitamin K play in bone health?

It is essential for bone mineralization and health.

How do anabolic steroids affect bone health?

They can promote increased bone density but may have adverse effects.