Chapter 6

Organic material consists of

Collagen and proteoglycans

-Dense solid outer layer surrounding bone -More matrix

Compact bone

The functional unit of this type of bone is an osteon (harvesian system)

Compact bone

Double layered outer layer of dense irregular connective tissue containing fibroblasts. Inner delicate layer has fewer fibers and contains chondroblasts

Perichondrium

Double layers connective tissue sheath surrounding cartilage

Perichondrium

What mineral are stored in the skeletal system?

Phosphorus, calcium, adipose tissue

Lacunae

Small space of cavity

What covers the ends of bones within some joints allowing for free movement

Smooth Cartilage

Vitamin ____ is necessary for osteoblasts to synthesize collage

Vitamin C

Entire skeleton renews every ____ years

10

Body support of the skeletal system

-Cartilage is firm and flexible in certain structures (Nose, external ear, thoracic cage, trachea) -Ligaments-holds bones together with strong bands of fibrous connective tissue

Cartilage growth where chondrocytes in perichondrium add new cartilage to the outside edge of existing cartilage

Appositional

How do bones increase in size?

Appositional growth

Two type of cartilage growth

Appositional, interstitial

Hyaline cartilage that covers ends of bone. Does not have perichondrium or blood vessels

Articular cartilage

The lamellae found in osteons are A.Circumferential Lamellae B.Concentric Lamellae C.Interstitial Lamellae

B.Concentric Lamellae

Some mesenchymal cells become A.Osteocytes B.Chondrocytes C.Stem cells D.your mom

C.Stem Cells

Each osteocyte is associated with others through __________. They receive nutrients through this because no blood vessels can penetrate the trabeculae

Canaliculi

What disease is caused by a vitamin D deficiency in children and adults?

Children-Ricketts Adults-Osteomalacia

-Form the outer surfaces of compact bone, which are thin plates that extend around the bone

Circumferential lamellae

Defect where maxillae doesn't form and is more common in males

Cleft lip

Defect where the embryonic plate fails to fuse and results in an opening in the roof of the mouth. Is more common in females

Cleft palette

How do nutrients transfer within perichondrium

Diffuse through cartilage matrix to reach chondrocytes

Ossification that starts as a hyaline cartilage model and is surrounded by perichondrium. forms the bones of the base of the skull, part of mandible

Endochondral ossification

3 types are carilage

Fibrous, hyaline, elastic

Bone with an interior framework of spongy bone between two layers of compact bone

Flat bones

Most bones in the body start out as a

Hyaline cartilage model

Inorganic Material consists of a calcium phosphate material called

Hydroxyapatite

Cartilage growth where chondrocytes in center of tissue divide and add more matrix between existing cells

Interstitial

What is formed where 2+bones come together

Joints

Chondroblasts form chondrocytes, rounded cells that occupy _______ within matrix

Lacunae

-Mature bone -has thin concentric sheets of lamellae

Lamellar bone

-Bone-building -extensive endoplasmic reticulum and numerous ribosomes

Osteoblasts

These bone cells secrete matrix vesicles, and contain high concentrations of CA2+ and PO43- which forms hydroxyapatite crystals

Osteoblasts

What bone cells produces collagen and proteoglycans which are packed into vessicles by the golgi apparatus and secreted by exocytosis

Osteoblasts

Cells that can become osteoblasts or chondroblasts that are located in the inner layer of the perichondrium and in layers of connective tissue that cover bone

Osteochondral progenitor cells

-Bone destroying -large multinucleated cells -These mature cells carry out bone reabsorption by accessing bone matrix. ---When they come in contact with bone surface they form attachment structure via interaction with the protein integrin, after structures called podosomes develop and forms a ruffled border

Osteoclasts

What cells are derived from stem cells in red bone marrow

Osteoclasts

Bone cell that is connected to others through cell extension and housed within the bone matrix in lacuna. Also have cell extensions housed in canaliculi

Osteocytes

Brittle bone disorder and have mutations that yield reduced or defective type one collagen

Osteogenesis imperfecta

____ delivers blood to the central canals of osteons and run perpendicular to central canals

Perforating canals

_____ contains blood vessels from periosteum and medullary cavity

Perforating canals

What disease is caused by a Vitamin C deficiency

Scurvy

Bone with a compact bone surface surrounding a spongy bone center with small spaces filled with marrow. -not elongated and do not have a diaphysis

Short and irregular bones

-Porous bone with less bone matrix -has interconnecting rods/plates called trabeculae and between that is spaces filled with bone marrow and blood vessels

Spongy bone

Thin and consist of several lamella with osteocytes located in lacunae between lamellae

Trabeculae

2 bones formed during ossification

Woven and lamellar bone

-First type of bone osteoblasts form during ossification -Fairly weak and collagen fibers are randomly oriented

Woven bone

Nutrition and hormones are factors that

affect bone growth

If amount of collagen is reduced and mineral is the primary constituent the bone will be

brittle

The flexible strength of bone occurs because of

collagen fibers

Hormones that affect bone growth

growth hormone, thyroid hormone, sex hormones

at the 5th week of development, embryonic mesenchyme condenses around the brain to form a membrane of connective tissue with randomly oriented collagen fibers (will eventually become cranial bones). Stops at age two

intramembranous ossification

If mineral in bone is reduced, collagen is the primary constituent and the bone will be

overly flexible

Air filled spaces lined with mucous membranes

sinuses

Functions of the skeletal system

support, protection, movement, storage, blood cell production