AGENDA MAY 9 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Chapter 5 TESTS – Make up tests 2. Functions and classification of bones 3. Skeletal System Diagrams – Label and Color Code different classifications of bone – Use all of the paper when creating our diagrams 4. Review and Homework – Skeletal System Diagrams DUE on Monday May 16

Question of the DAY How many bones are in the human body?

QotD Answer The adult human skeleton is comprised of 206 bones. – This count may vary due to physiological variation Infants have 270 bones at birth. – Some of these bones fuse together through growth and development stages reducing the bone count.

Copyright 2010, John Wiley & Sons, Inc. Chapter 6: Introduction to the Skeletal System

Copyright 2010, John Wiley & Sons, Inc. Chapter 6: Introduction to the Skeletal System The skeletal system provides a framework for all of the other structures in the body The skeletal system consists of bones, cartilages, ligaments, and tendons Each bone is a dynamic structure that contains multiple tissues Long term changes in bone at the tissue level can lead to an overall change in bone shape and strength

Copyright 2010, John Wiley & Sons, Inc. The Skeletal System Performs Six Key Functions in the Body Support - the structural framework of the body Protection - bones protect sensitive internal organs Movement - bones and joints allow muscular actions Mineral homeostasis - bones store calcium and other important minerals Blood cell production - all blood cells originate in the red bone marrow Triglyceride storage

Copyright 2010, John Wiley & Sons, Inc. The Six Key Functions of the Skeletal System Fall into Two Groups STRUCTURAL ROLES Support Protection Movement HOMEOSTASIS Mineral homeostasis Blood cell production Triglyceride storage

Copyright 2010, John Wiley & Sons, Inc. Bones are Classified into One of Five Basic Shapes

Classification of Bone Long Flat Short Irregular Sesamoid

Long bones - slightly curved for strength – femur, tibia, fibula, humerus, ulna, radius, phalanges Short bones - cube shaped – carpals and tarsals Flat bones - thin, protection, muscle attachment. – cranial bones, sternum, ribs, scapula

Irregular bones - complex shape – vertebrae, hip bones, facial bones, heel bone (calcaneus) Sesamoid bones – seed shaped – develop in tendons due to friction – palms of hands, soles of feet, patella

AGENDA May 10 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Chapter 5 TEST RESULTS 2. Long Bones 3. Skeletal System Diagrams – Label and Color Code different classifications of bone – Use all of the paper when creating our diagrams 4. Review and Homework – Skeletal System Diagrams DUE on Monday May 16

Anatomy of a long bone

Copyright 2010, John Wiley & Sons, Inc. Long Bones - Anatomy and Terminology Regions of a long bone – 1 diaphysis [the shaft] – 2 metaphyses – 2 epiphyses (proximal and distal) – 1 marrow cavity Surface tissues – Endosteum – Periosteum – Articular cartilage

Anatomy of a long bone Diaphysis=shaft Epiphysis=ends Metaphysis=between diaphysis and epiphysis Articular cartilage=hyaline cartilage covering the epiphysis Periosteum=layer of CT covering outside of bone Medullary cavity=marrow cavity contains yellow bone marrow Endosteum= layer of CT that lines medullary cavity

Copyright 2010, John Wiley & Sons, Inc. Long Bones - Anatomy and Terminology

Histology of bone What type of tissue is bone? Extracellular matrix= 25% water, 25% collagen fibers, 50% crystalllized mineral salts(hydroxyapatite) Hardness of bone is due to mineral salts Tensile strength (resistance to being stretched or torn apart) due to collagen fibers

AGENDA May 11 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Chapter 5 TEST RESULTS 2. Cell Types Compact and Spongy Bone 3. Skeletal System Diagrams – Label and Color Code different classifications of bone – Use all of the paper when creating our diagrams 4. Review and Homework – Skeletal System Diagrams DUE on Monday May 16

A&P Critical Thinking Extension Humans are the most advanced species on Earth. All living things are said to progressively evolve to best survive and reproduce in their environments. Is it possible that humans have degenerated in some way? (Consider Anatomy and Physiology of the Human Body)

Bone Mass and Growth “Modern human skeletons have shifted quite recently towards lighter—more fragile, if you like—bodies. It started when we adopted agriculture. Our diets changed. Our levels of activity changed,” says study co-author Habiba Chirchir, an anthropologist in the Smithsonian’s Human Origins Program.Habiba Chirchir “Modern humans had 50 to 75 percent less dense trabecular bone than chimpanzees” Thickness, volume, and surface area of cancellous bone is very indicative of bone joint strength. Read more: made-human-joint-bones-lighter /#1LUlt7GTpxkAeuuV.99http:// made-human-joint-bones-lighter /#1LUlt7GTpxkAeuuV.99

Bone Strength human-body-bone-strength-video.htm human-body-bone-strength-video.htm

Cells of Bone Osteogenic cells=unspecialized stem cells. Undergo cell division. Develops into osteoblast Osteoblast= cells that form bone do not undergo mitosis. Secrete collagen to build bone

Cells of Bone Osteocytes= mature bone cells derived from osteoblasts. No mitosis. Involved in exchange of nutrients and wastes in the blood. Osteoclasts=derived from monocytes(wbc) function in bone resorption (breakdown of matrix)

Copyright 2010, John Wiley & Sons, Inc. Osseous Tissue - Four Cell Types

AGENDA May 12 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Progress Reports DUE Wednesday May CONCEPT CHECK! 3. Compact and Spongy Bone 4. Review and Homework – Skeletal System Diagrams DUE on Monday May 16

CONCEPT CHECK May 12 1.These cells are unspecialized and develop into osteoblasts. 2. This bone cell does not divide and assists in the exchange of nutrients and waste. 3. What is the function of an osteoclast? 4. Osteoblasts secrete this substance to build strong bones.

CONCEPT CHECK ANSWERS May 12 3 POINTS EACH = 12 TOTAL POINTS 1. OSTEOGENIC CELLS 2. OSTEOCYTE 3. BONE RESORPTION – Break down of matrix 4. COLLAGEN

Copyright 2010, John Wiley & Sons, Inc. Osseous Tissue - Four Cell Types

Copyright 2010, John Wiley & Sons, Inc. Bones Contain Two Types of Osseous Tissues Compact bone is more dense – Provides strength of long bones. Spongy bone is the predominant tissue in flat bones – Strength due to trabeculae

Types of Osseous Tissue Compact - Forms the external layer of all bone Protects against the stress of weight and movement. Highly organized concentric ring structure allows nutrients and O2 to reach spaces.

Spongy bone- 20% of skeleton. -Does not contain osteons. -more spaces, less strength. - Matrix arranged in an irregular lattice work of thin plates called trabeculae. Think of them as trusses in a bridge

Spongy bone- 20% of skeleton. Short Flat Irregular bones Epiphyses of long bones -Red bone marrow of spongy bone  RBCs

AGENDA May 13 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Progress Reports DUE Wednesday May BONE Disorders Project – PROGERIA CBS News Clip 3. DIAGRAMS 4. Review and Homework – Skeletal System Diagrams DUE on Monday May 16

AGENDA May 16 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Progress Reports DUE Wednesday May DIAGRAMS DUE 3. DISSECTION - BRAIN 4. Review and Homework – Bone Disorders Project DUE on Monday May 23

AGENDA May 17 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Progress Reports DUE Wednesday May Bone Disorders Project TOPIC 3. DIAGRAMS DUE 4. Ossification 5. Review and Homework – Bone Disorders Project DUE on Monday May 23

Types of Osseous Tissue -osteon=repeating structural unit in compact bone - central canal(Haversial system)=open space containing blood vessels - concentric lamellae= rings in calcified matrix - canaliculi(little canals)=nutrients diffuse through these canals -interstitial lamellae=fill spaces between concentric lamellae

Copyright 2010, John Wiley & Sons, Inc. Bones Have an Extensive Blood Supply Osseous tissues have a rich blood supply, important in bone development and homeostatic regulation Bones also contain many sensory neurons, resulting in considerable pain when bones are injured

Copyright 2010, John Wiley & Sons, Inc. Compact Bone - Osteons as Structural Subunits

Copyright 2010, John Wiley & Sons, Inc. Spongy Bone - Trabeculae Appear Random But Are Not

Bone Formation Ossification is process by which bones form. Three instances 1. The initial formation of bones in the embryo and fetus 2. The growth of bones until their adult sizes are reached 3. The remodeling and repair of bones

Copyright 2010, John Wiley & Sons, Inc. Bones Form by Two Very Different Mechanisms 1. Intramembranous ossification – Tissue develops directly within sheet-like layers – Making of some flat bones (notably in the skull and mandible) 2. Endochondral ossification – Formation of bone cells inside a pre-existing hyaline cartilage model – Responsible for most of our bones (including all long bones)

CONCEPT CHECKMay What is the function of cortical bone? 2. Describe the structure of spongy bone that provides it with strength. 3. Why do bones require blood vessels? 4. What is the function of spongy bone found in the epiphyses of the long bones? 5. This process of ossification requires a cartilage model to produce new bone.

CONCEPT CHECKMay 18 5 Points EACH25 TOTAL POINTS 1. What is the function of cortical bone? – Protects against weight and movement 2. Describe the structure of spongy bone. – Irregular lattice work of trabeculae 3. Why do bones require blood vessels? – Living cells require oxygen and nutrients for cellular functions and growth 4. What is the function of spongy bone found in the epiphyses of the long bones? – Contains red bone marrow which produces RBCs 5. This process of ossification requires a cartilage model to produce new bone. – Endochondral

AGENDA May 18 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. CONCEPT CHECK 2. Progress Reports DUE TODAY! 3. Endochondral Ossification – Bone Growth Factors 4. Review and Homework – Bone Disorders Project DUE on Monday May 23

Copyright 2010, John Wiley & Sons, Inc. Bone Tissue Interactions Animation Bone Dynamics and Tissue You must be connected to the internet to run this animation.

Bone Remodeling Bones constantly recycle minerals – Calcium and Phosphate Resorption breaks down bone tissues – Minerals used by other cells in the body Deposition rebuilds bone tissue using minerals – Delivered through blood

Copyright 2010, John Wiley & Sons, Inc. Endochondral Ossification Step 1 -The cartilage model forms Step 2 – Model grows with growth of the body Step 3 - Primary ossification center forms when the artery provides blood. Medullary cavity forms. Step 4 - Blood vessel entry into epiphyses stimulates development of secondary ossification centers. Step 5 - Residual hyaline cartilage remains on the surface of epiphyses and at epiphyseal plate

1 Development of cartilage model Hyaline cartilage Perichondrium Proximal epiphysis Distal epiphysis Diaphysis 1 Development of cartilage model Growth of cartilage model 2 Hyaline cartilage Uncalcified matrix Calcified matrix Perichondrium Proximal epiphysis Distal epiphysis Diaphysis 1 Development of cartilage model Development of primary ossification center Growth of cartilage model 23 Hyaline cartilage Uncalcified matrix Calcified matrix Nutrient artery Perichondrium Proximal epiphysis Distal epiphysis Diaphysis Periosteum Primary ossification center Spongy bone 1 Hyaline cartilage Calcified matrix Periosteum (covering compact bone) Uncalcified matrix Calcified matrix Medullary cavity Nutrient artery and vein Nutrient artery Perichondrium Proximal epiphysis Distal epiphysis Diaphysis Development of cartilage model Development of primary ossification center Development of the medullary cavity Growth of cartilage model Periosteum Primary ossification center 234 Spongy bone Uncalcified matrix 1 Development of cartilage model Development of primary ossification center Development of the medullary cavity Growth of cartilage model 234 Hyaline cartilage Calcified matrix Periosteum (covering compact bone) Uncalcified matrix Calcified matrix Medullary cavity Nutrient artery and vein Nutrient artery Perichondrium Proximal epiphysis Distal epiphysis Diaphysis Periosteum Primary ossification center Secondary ossification center Nutrient artery and vein Uncalcified matrix Epiphyseal artery and vein Development of secondary ossification center 5 Spongy bone Uncalcified matrix 1 Articular cartilage Spongy bone Epiphyseal plate Secondary ossification center Nutrient artery and vein Uncalcified matrix Epiphyseal artery and vein Formation of articular cartilage and epiphyseal plate Development of secondary ossification center Development of cartilage model Development of primary ossification center Development of the medullary cavity Growth of cartilage model Hyaline cartilage Uncalcified matrix Calcified matrix Periosteum (covering compact bone) Uncalcified matrix Calcified matrix Medullary cavity Nutrient artery and vein Nutrient artery Perichondrium Proximal epiphysis Distal epiphysis Diaphysis Periosteum Primary ossification center Spongy bone

Copyright 2010, John Wiley & Sons, Inc. Growth of Long Bones Where is the site of long bone growth? – Epiphyseal Plate Replacement of cartilage with bone At 18–21 years old Area becomes fused indicating an end to growth Different bones fuse at different ages Age varies by gender and other factors

AGENDA May 19 OBJECTIVE: Identify factors that affect bone growth. 1. HOMEWORK – Diagrams of Endochondral Ossification 2. Bone Growth Factors 3. Review and Homework – TOMORROW  Project Research Day – Bone Disorders Project DUE on Monday May 23

Review of Endochondral Ossification Which steps are required to produce new bone?

Steps of Endochondral Ossification 1. Cartilage Model Forms 2. Cartilage grows with the bone as body grows 3. Primary Ossification Center – Blood delivers oxygen and nutrients 4. Secondary ossification center in epiphyses – Blood vessels 5. Bone formation occurs – Extends cartilage on the exterior ends of epiphyses – Fuses when bones reach maximum growth potential

Bone Growth Growth in length involves 2 major events -Replacement of cartilage on the epiphyseal plate(layer of hyaline cartilage in the metaphysis of growing bone) with osseous tissue -Replacement of cartilage on the diaphyseal side of the epiphyseal plate with osseous tissue.

Factors affecting growth and maintenance of bone Minerals – Calcium, phosphorus, magnesium, boron manganese Vitamins – D, A, B12, C Hormones -Human growth hormone(HGH) great effect on height -Sex hormones(estrogen/testosterone) promote activity in epiphyseal plate during puberty

Copyright 2010, John Wiley & Sons, Inc. Bone Formation Interactions Animation Bone Formation You must be connected to the internet to run this animation.

Copyright 2010, John Wiley & Sons, Inc. Bone Growth Interactions Animation Bone Elongation and Bone Widening You must be connected to the internet to run this animation.

1 Blood capillary Ossification center Mesenchymal cell Osteoblast Collagen fiber Development of ossification center Mandible Flat bone of skull 1 Blood capillary Ossification center Mesenchymal cell Osteoblast Osteocyte in lacuna Canaliculus Osteoblast Newly calcified bone matrix Development of ossification center Calcification Mandible Flat bone of skull 2 Collagen fiber 1 Blood capillary Ossification center Mesenchymal cell Osteoblast Development of ossification center Calcification Mandible Flat bone of skull 2 Collagen fiber Osteocyte in lacuna Canaliculus Osteoblast Newly calcified bone matrix Mesenchyme condenses Blood vessel Spongy bone trabeculae Osteoblast Formation of trabeculae 3 1 Blood capillary Ossification center Mesenchymal cell Osteoblast Mesenchyme condenses Blood vessel Spongy bone trabeculae Osteoblast Periosteum Spongy bone tissue Compact bone tissue Development of ossification center Calcification Formation of trabeculae Development of the periosteum Mandible Flat bone of skull Collagen fiber Osteocyte in lacuna Canaliculus Osteoblast Newly calcified bone matrix

Copyright 2010, John Wiley & Sons, Inc. Growth of Long Bones

Copyright 2010, John Wiley & Sons, Inc. Growth of Long Bones

Copyright 2010, John Wiley & Sons, Inc. Bone Remodeling Interactions Animation Bone Remodeling You must be connected to the internet to run this animation.

AGENDA May 23 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. Fractures 2. BONE DISORDERS Project Presentations 3. Homework and Review – Chapter 6 Test WEDNESDAY – MP4 Projects… See GOOGLE Classroom

Fractures Classified according to the position of the bone end after it breaks

Compound Bone ends penetrate the skin

Simple Bone ends do not penetrate the skin

Comminuted Bone fragments into 3 or more pieces. Common in elderly due to brittle bones

Greenstick Bone breaks incompletely, one side bent, one side broken. Which factors may contribute to this type of fracture?

Greenstick Which factors may contribute to this type of fracture? More collagen – Tensile strength / Flexibility Insufficient mineral deposits – Bone hardness Common in children

Spiral Ragged break caused by excessive twisting forces. Sports injury

Impacted One bone fragment is driven into the other

AGENDA May 24 OBJECTIVE: Examine the components that comprise the skeletal system and their functions. 1. BONE DISORDERS Project Presentations 2. Homework and Review – Chapter 6 Test WEDNESDAY – MP4 Projects… See GOOGLE Classroom

The BODY STORY Epi 5: CRASH M8rr0 M8rr0