Cartilage & Bone - Human Anatomy & Physiology - Chapter 6 - Tortora

General characteristics of CARTILAGE

very slow to heal avascular

What's the function of the periosteum?

Protects bone, assists in fracture repair, helps nourish bone tissue, and serves as an attachment point for ligaments and tendons.

Epiphyses

Proximal and distal ends of long bone. Core formed by spongy bone

Types of bone tissue.

Spongy & Compact

Fibrocartilage

Strongest/Toughest kind of cartilage Support and joining structures together. Strength and rigidity

Perichondrium

Surrounds the surface of most cartilage (Hyaline & Elastic) Contains blood vessels, nerves, and is a source of new cartilage

Diaphysis

shaft or body of a long bone

What cells are found in CARTILAGE?

Chondroblasts, chondrocytes, lacunae

Appositional growth

Grows around the OUTSIDE of cartilage. Starts later than interstitial growth but continues throughout childhood and adolescence

Mineral Salts found in bone

1. Calcium carbonate 2. Calcium phosphate (= Hydroxyapatite), most important/abundant!

What cells are found in bone tissue?

1. Osteoprogenitors (osteogenic) 2. Osteoblasts 3. Osteocytes 4. Osteoclasts

Bone matrix is made up of...

15% water, 30% collagen, 55% mineral salts

Cartilage

A connective tissue that is more flexible than bone and that protects the ends of bones and keeps them from rubbing together.

Epiglottis

A flap of tissue that seals off the windpipe and prevents food from entering.

Periosteum

A tough layer of connective tissue that surrounds the bone and serving as an attachment for tendons and muscles.

Osseous Tissue

Bone tissue. Type of Connective Tissue. Major structural and CT of the body.

Trabeculae

Columns found in Spongy Bone. Supports and protects red blood marrow. Has layers, lamellae, osteocytes in lacunae, canaliculi. Missing central and peripheral canals which provide nutrients. Blood vessels found on the outside of these structures.

Endosteum

Dense irregular connective tissue that lines the medullary cavities of long bones. A single layer

Where is elastic cartilage found?

Ears (auricle of the ear and auditory tubes), Epiglottis

Where is Hyaline Cartilage found?

Ends of long bones, anterior ends of ribs, *Joint surfaces Respiratory passageways Fetal skeleton

Describe cartilage's matrix.

Firm, rubbery, or gel-like consistency. A dense network of collagen and elastic fibers firmly embedded in chondroitin sulfate.

Osteoblasts

Forms bone matrix, secretes collagen fibers and other organic compounds. Initiates calcification. Found on the surface of the bone. Immature cell. Then forms osteocytes

Medullary Cavity

Hollow, cylindrical shape within the diaphysis that contains fatty yellow bone marrow and numerous blood vessels. Provides maximum strength with minimum weight.

What are the types of cartilage?

Hyaline, Fibrocartilage, and Elastic

What are the ways cartilage can grow?

Interstitial & Appositional

Osteocytes

Maintains bone tissue/matrix, and resides in the middle of it. Main cell type in cartilage Maintains its daily metabolism?

Elastic Cartilage

Maintains shape of certain structures lots of elastic fibers found here Provides strength and elasticity

Compact Bone

Most bones in body are this! Provides protection and support. *Resists the stresses produced by weight and movement. Osteon cells found here.

Hyaline Cartilage

Most common Weakest cartilage Collagen and elastic fibers. FX: provides smooth surfaces for movement at joints, flexibility, and support.

Where is Fibrocartilage found?

Places where the body has the greatest stress... Intervertebral Discs (Between backbone vertebrae), Knee, Pubic Symphysis, portions of tendons that insert into cartilage

Osteoclasts

Secretes collagenase and acids, which helps it function to break down bone or resorption of bone matrix on the surface. Helps regulate blood calcium level, target cells for drug therapy used to treat osteoporosis.

What is the function of red bone marrow?

To develop blood cells, adipocytes, fibroblasts, macrophages within a network of reticular fibers

Interstitial growth

When cartilage grows INSIDE or from the middle of the cartilage Happens when cartilage is young and pliable (childhood and adolescence)

Spongy Bone

aka Cancellous Bone Always the interior of the bone. Light weight, highly vascular Red & Yellow bone marrow

Osteon

aka Haversian System column of bone, laid down around blood vessels (which feeds nutrients to bone tissue). outside of the bone, runs the length of the diaphysis. Not static formation but changes over time in response to physical demands placed on the skeleton.

Metaphysis

between the diaphysis and epiphysis. Contains growth plates. Hyaline cartilage to grow diaphysis.

How is cartilage different from loose and dense connective tissues?

can endure considerably more stress than other CTs

Yellow Bone Marrow

lots of adipocytes found here. Stores triglycerides - which are potential chemical energy reserve.

Red Bone Marrow

lots of blood cells found here. Site where hemopoiesis (blood cell and platelet production) occurs in adults. Found in hips, ribs, sternum, vertebrae, and the ends of humerus and femur.

Articular Cartilage

reduces friction, absorbs shock. Thin layer of Hyaline cartilage covering part of the epiphysis. Lacks perichondrium and blood vessels

Lacunae

small, hallow space that contains chondrocytes in cartilage

Osteoprogenitors (osteogenic)

unspecialized bone stem cells gives rise to osteoblasts Found in periosteum, endosteum, and canals in bone that contain blood vessels

Where is Pubic Symphysis?

where hip bones join anteriorly