A&P 1 Chapter 6 Objectives

What are the 3 types of cartilage?

Hyaline, elastic, fibrocartilage

Where can hyaline cartilage be found?

Ends of bones, nose, trachea

Where can elastic cartilage be found?

External ear and epiglottis

Where can fibrocartilage be found?

Sites subjected to pressure and stretch

What makes hyaline cartilage resilient?

Fine collagen fibers

What makes elastic cartilage resilient?

Resemble hyaline cartilage, more stretchy

What makes fibrocartilage resilient?

Chondrocytes and thick collagen fibers

Describe short bone

Roughly cube shaped, includes sesamoid bones that alter direction of pull or reduce friction

Describe long bone

Elongated shape with a shaft and two ends

Describe flat bones

Thin, flat, usually curved

Describe irregular bones

Complicated shape

What is an example of a long bone?

Limb bones, like femur

What is an example of a short bone?

Wrist bones

What is an example of a flat bone?

Sternum

What is an example of an irregular bone?

Vertebrae

What are the major regions of the skeleton?

Axial and appendicular

What is the function of the axial skeleton?

Protect, support, or carry other body parts

What is the function of the appendicular skeleton?

Attached to limbs that help us move

What are the functions of the skeleton?

Support, hematopoisis, hormone production, protection, movement, mineral and growth factor storage, triglyceride storage

Describe the function of mineral storage of the skeleton

Bone is a reservoir for minerals like calcium and phosphate that are released into the bloodstream when needed

Describe the function of hematopoiesis of the skeleton

Blood cell formation

Describe the function of triglyceride storage of the skeleton

Fat is a source of energy for the body

Describe the function of hormone production of the skeleton

Osteocalcin is produced, regulateing bone formation and stimulates adiponectin

What are the gross anatomy components of a typical long bone?

Diaphysis, epiphyses, membranes. blood vessels and nerves

Describe the diaphysis in typical long bones

Shaft of bone that is made of a thick collar of compact bone that surrounds the marrow cavity which contains yellow marrow

Describe the epiphyses in typical long bones

Bone ends that have an outer shell of compact bone with a spongy bone interior, covered by a thin layer of articular cartilage

Describe the membranes in typical long bones

The periosteum covers the entire bone, supplied by nerve fibers and blood vessels

Describe the blood vessels and nerves in typical long bones

Nutrient artery and nutrient vein supply the diaphysis through the nutrient foramen

What is the location and function of red marrow?

Between trabeculae of spongy bones in flat bones and heads of long bones, hematopoisis

What is the location and function of yellow marrow?

Medullary cavity of the diaphysis, store fat

What is the location and function of articular cartilage?

Covers the ends of bones that form joints, provide smooth surface to facilitate joint movement

What is the location and function of periosteum?

Covers the external surface of the entire bone except joint surfaces, provides blood supply to bone

What is the location and function of endosteum?

Covers internal spongy bone surfaces, facilitates bone growth

What is the function and location of trabeculae?

Inside spongy bone, helps the bone resist stress

What is the function and location of compact bone?

Outer layer of long bones, provides strength and protection

What is the function and location of spongy bone?

Ends of long bones, provide structural support

What is the histology of the compact bone (osteon structure)?

Contains lamellae, interstitial lamellae, lacuna, and central canal

What is the lamellae?

Layers of bone tissue

What is the lacuna?

Where the cell lives

What is the central canal?

Blood vessels and nerves that provides tissue with nutrients

Describe the gross anatomy of a typical flat bone

Contains two thin plates of compact bone enclosing a spongy bone layer

What are the organic components of bone?

Carbon, oxygen, osteoids that contain proteins and enzymes

What are the inorganic components of bone?

Calcium and phosphate, including hydroxyapatite that forms the basis of bone tissue

What is the basic difference between intramembranous ossification and endochondral ossification?

Intramembranous ossification is when a bone develops to form a fibrous membrane, while in endochondral ossification is when a bone develops by replacing a hyaline cartilage

Describe the process of long bone growth that occurs at the epiphyseal plates

The epiphyseal plate is a layer of hyaline cartilage where ossification occurs, allowing the diaphysis to grow in length

Describe the differences between appositional growth and longitudinal growth

Appositional growth makes the bones thicker while longitudinal growth makes the bones longer

Where are osteoblasts located?

Periosteum and endosteum

Where are osteocytes located?

Lacuna

Where are osteoclasts located?

Sites of bone resorption

What is the remodeling function of osteoblasts?

Bone forming cells and matrix calcification

What is the remodeling function of osteocytes?

Monitor and maintain bone matrix

What is the remodeling function of osteoclasts?

Bone resorption, breaking down old or damaged bone tissue

Explain how hormones regulate bone remodeling

Parathyroid gland detects falling blood calcium levels and secretes PTH that tells osteoclasts to degrade bone and release more blood calcium into blood

Explain how physical stress / gravity regulates bone remodeling

Wolff’s law says that the bone grows or remodels according to mechanical demands placed upon it, signaling osteocytes to build new bone tissue or break down old bone tissue