Osteology is the study of bones. Bones provide structure, protection, movement, mineral storage, blood cell formation, and energy storage. Bone tissue consists of cells within an organic collagen-rich extracellular matrix as well as an inorganic mineral component. Cortical bone forms the dense outer layer of long bones and has concentric osteons. Cancellous or spongy bone is found at the ends of long bones and in flat and irregular bones. Bones experience both compression and tension forces and have adapted structures like osteons and layered lamellae to withstand these stresses.
Bone is a specialized connective tissue composed of calcified bone matrix and three main cell types: osteocytes found in bone matrix lacunae and canaliculi, osteoblasts which synthesize bone matrix, and osteoclasts which resorb bone. Bone provides structure and protection, supports muscle attachment, stores minerals, and enables movement through leveraging of muscles. It is continually remodeled through the coordinated actions of osteoblasts and osteoclasts, forming concentric osteons through either intramembranous or endochondral ossification.
CONTENTS
FORMATION OF BONE
CLASSIFICATION OF BONES
STRUCTURE OF BONE
BLOOD SUPPLY
COMPOSITION OF BONE
FRACTURE HEALING
CARTILAGE
TYPES OF CARTILAGE
BONE (syn – Os; Osteon)
Osseous tissue, a specialised form of dense connective
tissue consisting of bone cells (osteocytes)
Embedded in a matrix of calcified intercelluar
substance
Bone matrix contains collagen fibres and the minerals
calcium phosphate and calcium carbonate
This document provides an overview of bone histology. It defines bone as a mineralized connective tissue composed of bone matrix and three cell types: osteoblasts, osteocytes, and osteoclasts. It describes the microscopic structure of compact and spongy bone, including osteons, central canals, lamellae, and trabeculae. It explains the functions of osteoblasts in bone formation, osteoclasts in bone resorption, and osteocytes in bone maintenance. Finally, it discusses the periosteum and endosteum, which cover the external and internal bone surfaces and provide nutrition and new osteoblasts.
There are two main types of bone tissue: compact bone and spongy bone. Compact bone looks solid and is densely packed, consisting of concentric cylindrical layers surrounding central canals. Spongy bone has a porous, sponge-like appearance due to trabeculae that form bone spicules and columns, leaving spaces between them. Both tissues have different microscopic structures that give them their distinct macroscopic appearances. Bone tissue serves important functions as the main structural support of the body, protecting internal organs, providing attachment sites for tendons and muscles, housing bone marrow, and storing minerals.
Cartilage is a specialized connective tissue composed of chondrocytes embedded in an extracellular matrix. It is avascular and provides structure, support, and acts as a shock absorber. There are three main types of cartilage - hyaline cartilage found in joints, elastic cartilage in the ear, and fibrocartilage in intervertebral discs. Hyaline cartilage contains collagen type II and glycosaminoglycans that allow it to withstand compression. Elastic cartilage contains elastic fibers that give it flexibility. Fibrocartilage contains collagen types I and II and connects bones together.
This document provides an overview of bone anatomy, physiology, and pathology. It discusses the following key points in 3 sentences or less:
- Bone is composed of inorganic minerals (hydroxyapatite crystals) and organic collagen fibers, which provide strength and allow bone to withstand compression and tension. Bone develops through two processes: intramembranous and endochondral ossification. Bone remodeling is a continuous process where old bone is resorbed and new bone is formed, enabling calcium homeostasis and repair of microdamage.
The document provides information about the muscular system. It discusses the different types of muscles in the body including skeletal, cardiac, and smooth muscles. Skeletal muscles are voluntary and attach to bones, enabling movement. They comprise about 40-50% of body weight. Cardiac muscle is only found in the heart and has interconnected fibers. Smooth muscle is involuntary and found in organs like the stomach and intestines. The document also describes muscle properties like contractility and elasticity. It discusses muscle fiber types, innervation, the sliding filament theory of contraction, and age-related changes in muscles.
This document provides an overview of bone structure and formation. It discusses the two types of ossification - intramembranous and endochondral. Intramembranous ossification forms flat bones of the skull directly from mesenchymal tissue, while endochondral ossification involves cartilage models that are later replaced by bone. Bone cells, blood supply, composition and fracture healing are also summarized. The document classifications bones by shape, developmental origin, and microscopic and macroscopic structure.
Bone is a specialized connective tissue composed of calcified bone matrix and three main cell types: osteocytes found in bone matrix lacunae and canaliculi, osteoblasts which synthesize bone matrix, and osteoclasts which resorb bone. Bone provides structure and protection, supports muscle attachment, stores minerals, and enables movement through leveraging of muscles. It is continually remodeled through the coordinated actions of osteoblasts and osteoclasts, forming concentric osteons through either intramembranous or endochondral ossification.
CONTENTS
FORMATION OF BONE
CLASSIFICATION OF BONES
STRUCTURE OF BONE
BLOOD SUPPLY
COMPOSITION OF BONE
FRACTURE HEALING
CARTILAGE
TYPES OF CARTILAGE
BONE (syn – Os; Osteon)
Osseous tissue, a specialised form of dense connective
tissue consisting of bone cells (osteocytes)
Embedded in a matrix of calcified intercelluar
substance
Bone matrix contains collagen fibres and the minerals
calcium phosphate and calcium carbonate
This document provides an overview of bone histology. It defines bone as a mineralized connective tissue composed of bone matrix and three cell types: osteoblasts, osteocytes, and osteoclasts. It describes the microscopic structure of compact and spongy bone, including osteons, central canals, lamellae, and trabeculae. It explains the functions of osteoblasts in bone formation, osteoclasts in bone resorption, and osteocytes in bone maintenance. Finally, it discusses the periosteum and endosteum, which cover the external and internal bone surfaces and provide nutrition and new osteoblasts.
There are two main types of bone tissue: compact bone and spongy bone. Compact bone looks solid and is densely packed, consisting of concentric cylindrical layers surrounding central canals. Spongy bone has a porous, sponge-like appearance due to trabeculae that form bone spicules and columns, leaving spaces between them. Both tissues have different microscopic structures that give them their distinct macroscopic appearances. Bone tissue serves important functions as the main structural support of the body, protecting internal organs, providing attachment sites for tendons and muscles, housing bone marrow, and storing minerals.
Cartilage is a specialized connective tissue composed of chondrocytes embedded in an extracellular matrix. It is avascular and provides structure, support, and acts as a shock absorber. There are three main types of cartilage - hyaline cartilage found in joints, elastic cartilage in the ear, and fibrocartilage in intervertebral discs. Hyaline cartilage contains collagen type II and glycosaminoglycans that allow it to withstand compression. Elastic cartilage contains elastic fibers that give it flexibility. Fibrocartilage contains collagen types I and II and connects bones together.
This document provides an overview of bone anatomy, physiology, and pathology. It discusses the following key points in 3 sentences or less:
- Bone is composed of inorganic minerals (hydroxyapatite crystals) and organic collagen fibers, which provide strength and allow bone to withstand compression and tension. Bone develops through two processes: intramembranous and endochondral ossification. Bone remodeling is a continuous process where old bone is resorbed and new bone is formed, enabling calcium homeostasis and repair of microdamage.
The document provides information about the muscular system. It discusses the different types of muscles in the body including skeletal, cardiac, and smooth muscles. Skeletal muscles are voluntary and attach to bones, enabling movement. They comprise about 40-50% of body weight. Cardiac muscle is only found in the heart and has interconnected fibers. Smooth muscle is involuntary and found in organs like the stomach and intestines. The document also describes muscle properties like contractility and elasticity. It discusses muscle fiber types, innervation, the sliding filament theory of contraction, and age-related changes in muscles.
This document provides an overview of bone structure and formation. It discusses the two types of ossification - intramembranous and endochondral. Intramembranous ossification forms flat bones of the skull directly from mesenchymal tissue, while endochondral ossification involves cartilage models that are later replaced by bone. Bone cells, blood supply, composition and fracture healing are also summarized. The document classifications bones by shape, developmental origin, and microscopic and macroscopic structure.
The document discusses the skeletal system and bones. It covers the structure and function of bones, classification of bones, bone tissues, bone cells, bone growth and healing, joints, and common bone diseases. The skeletal system includes bones, cartilage, ligaments, and joints. It is divided into the axial skeleton which includes the skull, vertebral column, ribs, and thoracic cage, and the appendicular skeleton which includes the limbs and their attachments.
This document provides an overview of connective tissue. It discusses the main cells found in connective tissue, including fibroblasts, adipocytes, macrophages, mast cells, plasma cells, and leukocytes. It also describes the main fibers - collagen, reticular, and elastic fibers - and ground substance. Finally, it outlines the main types of connective tissue, including connective tissue proper (loose and dense connective tissue), supporting connective tissue (cartilage and bone), and fluid connective tissue (blood). Loose connective tissue, also called areolar tissue, is characterized as having cells, fibers and ground substance in roughly equal parts and serving to bind organs and fill spaces between tissues.
Introduction of bones, types, structureZENITH PARMAR
Bones are living tissues made of connective tissues and minerals. They perform many functions including supporting the body, protecting organs, allowing movement, and producing blood cells. The adult skeleton contains 206 bones that form through two processes - intramembranous formation which produces flat bones like the skull, and endochondral formation where cartilage is replaced by bone. Bones continuously remodel through the actions of bone-forming osteoblasts and bone-resorbing osteoclasts.
Anatomy unit 7 physiology of the skeletal systemwanted1361
The skeletal system consists of 206 bones that provide structure, protection, movement, storage, and blood cell formation. Bones are made of collagen, hydroxyapatite, and other tissues. The skeletal system is divided into the axial skeleton (skull and vertebrae) and appendicular skeleton (limbs). Long bones have an epiphysis, diaphysis, articular cartilage, and epiphyseal plate. Joints connect bones and include ligaments, cartilage, and fluid-filled capsules. Bone tissue contains periosteum, compact bone, spongy bone, marrow cavity, and Haversian systems. Bones develop from cartilage and are constantly remodeling through osteoblasts, osteoclasts,
The topic includes:
definition and function bone
classification of bone according to shape, development, region and structure
gross structure of long bone
parts of a bone (epiphysis, diaphysis, metaphysis and epiphysial plate of cartilage)
blood supply of bone
growth of a long bone
Introduction,structure,funtions and nutrition of hyaline cartilagePramod Yspam
Hyaline cartilage is a type of cartilage that provides stiff yet flexible support in joints, ribs, trachea, and other body structures. It consists of chondrocytes within a matrix of collagen fibers and proteoglycans. Articular cartilage covering the ends of bones in joints is a key example that absorbs pressure and reduces friction between bones. Its avascular nature means it relies on diffusion from synovial fluid and nearby bone for nutrition.
The skeletal system is composed of bones and associated tissues that provide structure, protection, movement, and mineral storage. Bones are living tissues composed of cells, collagen fibers, and minerals. There are four types of bones - long, short, flat, and irregular - with different structures adapted to their functions. Bones develop through intramembranous or endochondral ossification and are remodeled throughout life by bone cells.
Bone is a mineralized connective tissue that forms the endoskeleton of vertebrates. It has both compact and spongy structures and develops through either membranous or endochondral ossification. Bone is made up of osteoprogenitor cells, osteoblasts, osteocytes, and osteoclasts. Osteoblasts form new bone tissue while osteoclasts resorb old or damaged bone. The intricate blood supply through nutrient arteries is essential for bone growth and healing. Fractures heal through the formation of a hematoma, fibrocartilaginous callus, bony callus, and remodeling into secondary bone.
There are two types of bone tissue: compact bone and spongy bone. Compact bone contains concentric rings surrounding haversian canals, while spongy bone is less dense and contains thin bone columns. Bones come in long, short, flat, and irregular shapes. Long bones have a diaphysis made of compact bone, epiphyses containing spongy bone, articular cartilage at the ends, a periosteum outer layer, and medullary cavity containing marrow. Key bone markings include heads, condyles, epicondyles, and trochanters for muscle attachment and articulation.
Bone tissue is a specialized form of connective tissue composed of cells and a mineralized extracellular matrix. The matrix is made up of collagen fibers and hydroxyapatite crystals that give bone its rigidity. There are two types of bone tissue: compact bone which forms the dense outer layer, and spongy or cancellous bone which is found at the ends of long bones and has a spongy, mesh-like structure. Bones develop through two processes - intramembranous ossification which forms flat bones, and endochondral ossification where cartilage is replaced by bone to form most other bones including long bones.
Bones grow in length through endochondral ossification at the epiphyseal plate. Chondrocytes proliferate and are replaced by bone on the diaphyseal side, increasing bone length over time. Many factors influence bone growth, including nutrients, hormones, and weight-bearing exercise. Bones also remodel throughout life, with osteoclasts resorbing old bone and osteoblasts depositing new bone to maintain strength.
There are two types of bone ossification: intramembranous and endochondral. Intramembranous ossification forms bones like the skull and clavicles directly in connective tissue. Endochondral ossification replaces cartilage with bone to form long bones. This process begins with mesenchymal cells forming cartilage, which then undergoes interstitial and appositional growth. Osteoblasts eventually deposit bone matrix around the calcified cartilage, forming trabeculae and replacing the cartilage with bone from the primary ossification center outward.
Bone is a composite material formed mostly of calcium phosphate. There are two types of bone tissue: compact bone and spongy bone. Cortical bone accounts for 80% of the total bone mass in the adult skeleton. There are two processes of bone formation: intramembranous ossification which forms flat bones of the skull, and endochondral ossification which forms most other bones through a cartilage model. Bone is constantly remodeled through the actions of osteoblasts which build bone and osteoclasts which break it down.
This document provides an overview of general histology, covering topics like cytology, embryology, tissues, blood, and more. It begins with definitions of noncellular structures like symplasts and syncytium. It then discusses cells in detail, including their membranes, organelles, and inclusions. The document covers embryology, describing the stages of fertilization, cleavage, gastrulation, and histogenesis. It provides information on the four basic tissues - epithelial, connective, muscular and nervous. Specific cell and tissue types are defined such as erythrocytes, stratified squamous epithelium, and exocrine glands.
This document summarizes the structure and types of muscle tissue in the human body. It discusses that muscle is composed of actin and myosin filaments that slide to produce movement. There are three main types of muscle: skeletal, cardiac, and smooth muscle. Skeletal muscle is striated and voluntary, attaching to bones via tendons. Cardiac muscle is also striated but involuntary, forming the walls of the heart. Smooth muscle is non-striated and involuntary, found within organs like the digestive tract.
Cartilage functions to support the body, provide a framework for attachment of muscles, protect underlying tissues, and provide flexibility. There are three main types of cartilage - hyaline, elastic, and fibrous - which differ in their fiber composition and density. Hyaline cartilage is the most common and found at joints, nose, trachea, and fetal skeleton. Elastic cartilage is rare but found in ear and epiglottis where its elasticity is important. Fibrous cartilage has strong collagen fibers and acts as a shock absorber in joints, discs, and meniscus.
Bone is a composite material made up of cells and an extracellular matrix. At the micro level, bone contains osteoblasts that build bone tissue, osteoclasts that resorb bone, and osteocytes embedded in the matrix. The matrix is made of collagen fibers mineralized with hydroxyapatite crystals. Bones can be classified by their macro structure as long, short, flat, or irregular. Long bones have a diaphysis and epiphyses. Bone structure is adapted to its mechanical functions according to Wolff's law.
Tendons consist of parallel bundles of collagen fibers that provide great tensile strength to anchor muscles to bones. Ligaments contain bundles of elastic fibers and some collagen, making them more flexible than tendons but offering less strength to hold bones together. Fibroblasts secrete the fibers and ground substance of connective tissue and are called fibrocytes when not actively engaged in synthesis. The poor blood supply to tendons and ligaments affects their behavior in the body.
Cartilage:
Cartilage is a specialized type of dense collective tissue designed to give support , bear weight and withstand tension , torsion , and bending.
General Features :
• Cartilage supports regions of body that requires flexibility.
• Non nervous structure
• Avascular
• Very poor regeneration power
• Usually surrounded by pericondrium (dense irregular connective tissue surrounding cartilage) except fibro cartilage.
Classification:
Hyaline cartilage
Elastic cartilage
Fibro cartilage
Fibro Cartilage :
White colored, tough cartilage containing dense connective tissue and collagen fibers often known as intervertebral discs is called fibro cartilage.
Structure :
Fibro cartilage consists of chondrocytes dispersed among bundles of type 1 collagen fibers.
Chondrocytes are present in lacunae (cavity).
The arrangement of cells is different from all other type of cartilages.
Chondrocytes are arranged in parallel rows of 2, 4 or 6 cells.
These rows of cells are called isogenous cell groups.
Chemical Compounds Present :
Proteoglycans rich in sulphated glucosaminoglycans especially
Chondroiton sulphate
Dermatan sulphate
Stain :
Due to the abundance of collagen type 1 fibers , the matrix of fibrocartilage stains intensely acidophilic/eosinophilic. (since collagen is basic in nature)
Stained by EOSIN which is pink in color.
Chondrocytes are stained in purple usually by HEMATOXYLIN and looks purple in color due to acidic nature of large centeral nucleus present.
Occurrence in body :
Intervertebral disc
Disc of pubic symphysis
Menisci of knee joint
Sternoclavicular joint
Temporomandibular joint
Ligamentum tere
Labrum glenoidale
Labrum acetabulare
Fibrocartilage is also found at places where tendons and ligaments attach to bones.
Disorders:
Degeneration of fibrocartilage is seen in degenerative disc disease.
A fibrocartilaginous embolism (FCE) is an unusual cause of spinal cord and cerebral ischemia (insufficient bloodsupply). Symptoms may include sudden, severe pain in the neck and/or back; progressive weakening reduced sensation and paralysis. It may be caused by the blocking of an artery interrupting vascular supply.
A herniated disk is a disk that ruptures. This allows the jelly-like center of the disk to leak, irritating the nearby nerves. This can cause sciatica or back pain.
References:
http://www.nlm.nih.gov/medlineplus/herniateddisk.html
http://www.ncbi.nlm.nih.gov/pubmed/3289246
histology by laiq hussaain
Lecture 2 (anatomical and histological of bone )Ayub Abdi
The document summarizes the gross anatomy and microstructure of bone. It describes the parts of long bones including the diaphysis, epiphyses, and growth plates. It explains the differences between compact and spongy bone and their histological features. It also outlines the four main types of bone cells - osteoblasts, osteocytes, osteoclasts, and osteogenic cells - and their functions in bone formation and resorption.
The skeletal system is composed of bones and associated tissues that perform several essential functions:
1. Support - Bones provide structural support for the body and protection for internal organs.
2. Movement - Skeletal muscles use bones as levers to enable movement of the body.
3. Mineral storage - Bones store minerals like calcium and phosphorus.
There are over 200 bones in the human body that are classified as long, short, flat, or irregular. Bones are living tissues composed of cells like osteoblasts, osteocytes, and osteoclasts embedded in an organic bone matrix and inorganic minerals. Compact bone forms the dense outer layer while spongy bone composes the inner layer. Long bones have
The document discusses the skeletal system and bones. It covers the structure and function of bones, classification of bones, bone tissues, bone cells, bone growth and healing, joints, and common bone diseases. The skeletal system includes bones, cartilage, ligaments, and joints. It is divided into the axial skeleton which includes the skull, vertebral column, ribs, and thoracic cage, and the appendicular skeleton which includes the limbs and their attachments.
This document provides an overview of connective tissue. It discusses the main cells found in connective tissue, including fibroblasts, adipocytes, macrophages, mast cells, plasma cells, and leukocytes. It also describes the main fibers - collagen, reticular, and elastic fibers - and ground substance. Finally, it outlines the main types of connective tissue, including connective tissue proper (loose and dense connective tissue), supporting connective tissue (cartilage and bone), and fluid connective tissue (blood). Loose connective tissue, also called areolar tissue, is characterized as having cells, fibers and ground substance in roughly equal parts and serving to bind organs and fill spaces between tissues.
Introduction of bones, types, structureZENITH PARMAR
Bones are living tissues made of connective tissues and minerals. They perform many functions including supporting the body, protecting organs, allowing movement, and producing blood cells. The adult skeleton contains 206 bones that form through two processes - intramembranous formation which produces flat bones like the skull, and endochondral formation where cartilage is replaced by bone. Bones continuously remodel through the actions of bone-forming osteoblasts and bone-resorbing osteoclasts.
Anatomy unit 7 physiology of the skeletal systemwanted1361
The skeletal system consists of 206 bones that provide structure, protection, movement, storage, and blood cell formation. Bones are made of collagen, hydroxyapatite, and other tissues. The skeletal system is divided into the axial skeleton (skull and vertebrae) and appendicular skeleton (limbs). Long bones have an epiphysis, diaphysis, articular cartilage, and epiphyseal plate. Joints connect bones and include ligaments, cartilage, and fluid-filled capsules. Bone tissue contains periosteum, compact bone, spongy bone, marrow cavity, and Haversian systems. Bones develop from cartilage and are constantly remodeling through osteoblasts, osteoclasts,
The topic includes:
definition and function bone
classification of bone according to shape, development, region and structure
gross structure of long bone
parts of a bone (epiphysis, diaphysis, metaphysis and epiphysial plate of cartilage)
blood supply of bone
growth of a long bone
Introduction,structure,funtions and nutrition of hyaline cartilagePramod Yspam
Hyaline cartilage is a type of cartilage that provides stiff yet flexible support in joints, ribs, trachea, and other body structures. It consists of chondrocytes within a matrix of collagen fibers and proteoglycans. Articular cartilage covering the ends of bones in joints is a key example that absorbs pressure and reduces friction between bones. Its avascular nature means it relies on diffusion from synovial fluid and nearby bone for nutrition.
The skeletal system is composed of bones and associated tissues that provide structure, protection, movement, and mineral storage. Bones are living tissues composed of cells, collagen fibers, and minerals. There are four types of bones - long, short, flat, and irregular - with different structures adapted to their functions. Bones develop through intramembranous or endochondral ossification and are remodeled throughout life by bone cells.
Bone is a mineralized connective tissue that forms the endoskeleton of vertebrates. It has both compact and spongy structures and develops through either membranous or endochondral ossification. Bone is made up of osteoprogenitor cells, osteoblasts, osteocytes, and osteoclasts. Osteoblasts form new bone tissue while osteoclasts resorb old or damaged bone. The intricate blood supply through nutrient arteries is essential for bone growth and healing. Fractures heal through the formation of a hematoma, fibrocartilaginous callus, bony callus, and remodeling into secondary bone.
There are two types of bone tissue: compact bone and spongy bone. Compact bone contains concentric rings surrounding haversian canals, while spongy bone is less dense and contains thin bone columns. Bones come in long, short, flat, and irregular shapes. Long bones have a diaphysis made of compact bone, epiphyses containing spongy bone, articular cartilage at the ends, a periosteum outer layer, and medullary cavity containing marrow. Key bone markings include heads, condyles, epicondyles, and trochanters for muscle attachment and articulation.
Bone tissue is a specialized form of connective tissue composed of cells and a mineralized extracellular matrix. The matrix is made up of collagen fibers and hydroxyapatite crystals that give bone its rigidity. There are two types of bone tissue: compact bone which forms the dense outer layer, and spongy or cancellous bone which is found at the ends of long bones and has a spongy, mesh-like structure. Bones develop through two processes - intramembranous ossification which forms flat bones, and endochondral ossification where cartilage is replaced by bone to form most other bones including long bones.
Bones grow in length through endochondral ossification at the epiphyseal plate. Chondrocytes proliferate and are replaced by bone on the diaphyseal side, increasing bone length over time. Many factors influence bone growth, including nutrients, hormones, and weight-bearing exercise. Bones also remodel throughout life, with osteoclasts resorbing old bone and osteoblasts depositing new bone to maintain strength.
There are two types of bone ossification: intramembranous and endochondral. Intramembranous ossification forms bones like the skull and clavicles directly in connective tissue. Endochondral ossification replaces cartilage with bone to form long bones. This process begins with mesenchymal cells forming cartilage, which then undergoes interstitial and appositional growth. Osteoblasts eventually deposit bone matrix around the calcified cartilage, forming trabeculae and replacing the cartilage with bone from the primary ossification center outward.
Bone is a composite material formed mostly of calcium phosphate. There are two types of bone tissue: compact bone and spongy bone. Cortical bone accounts for 80% of the total bone mass in the adult skeleton. There are two processes of bone formation: intramembranous ossification which forms flat bones of the skull, and endochondral ossification which forms most other bones through a cartilage model. Bone is constantly remodeled through the actions of osteoblasts which build bone and osteoclasts which break it down.
This document provides an overview of general histology, covering topics like cytology, embryology, tissues, blood, and more. It begins with definitions of noncellular structures like symplasts and syncytium. It then discusses cells in detail, including their membranes, organelles, and inclusions. The document covers embryology, describing the stages of fertilization, cleavage, gastrulation, and histogenesis. It provides information on the four basic tissues - epithelial, connective, muscular and nervous. Specific cell and tissue types are defined such as erythrocytes, stratified squamous epithelium, and exocrine glands.
This document summarizes the structure and types of muscle tissue in the human body. It discusses that muscle is composed of actin and myosin filaments that slide to produce movement. There are three main types of muscle: skeletal, cardiac, and smooth muscle. Skeletal muscle is striated and voluntary, attaching to bones via tendons. Cardiac muscle is also striated but involuntary, forming the walls of the heart. Smooth muscle is non-striated and involuntary, found within organs like the digestive tract.
Cartilage functions to support the body, provide a framework for attachment of muscles, protect underlying tissues, and provide flexibility. There are three main types of cartilage - hyaline, elastic, and fibrous - which differ in their fiber composition and density. Hyaline cartilage is the most common and found at joints, nose, trachea, and fetal skeleton. Elastic cartilage is rare but found in ear and epiglottis where its elasticity is important. Fibrous cartilage has strong collagen fibers and acts as a shock absorber in joints, discs, and meniscus.
Bone is a composite material made up of cells and an extracellular matrix. At the micro level, bone contains osteoblasts that build bone tissue, osteoclasts that resorb bone, and osteocytes embedded in the matrix. The matrix is made of collagen fibers mineralized with hydroxyapatite crystals. Bones can be classified by their macro structure as long, short, flat, or irregular. Long bones have a diaphysis and epiphyses. Bone structure is adapted to its mechanical functions according to Wolff's law.
Tendons consist of parallel bundles of collagen fibers that provide great tensile strength to anchor muscles to bones. Ligaments contain bundles of elastic fibers and some collagen, making them more flexible than tendons but offering less strength to hold bones together. Fibroblasts secrete the fibers and ground substance of connective tissue and are called fibrocytes when not actively engaged in synthesis. The poor blood supply to tendons and ligaments affects their behavior in the body.
Cartilage:
Cartilage is a specialized type of dense collective tissue designed to give support , bear weight and withstand tension , torsion , and bending.
General Features :
• Cartilage supports regions of body that requires flexibility.
• Non nervous structure
• Avascular
• Very poor regeneration power
• Usually surrounded by pericondrium (dense irregular connective tissue surrounding cartilage) except fibro cartilage.
Classification:
Hyaline cartilage
Elastic cartilage
Fibro cartilage
Fibro Cartilage :
White colored, tough cartilage containing dense connective tissue and collagen fibers often known as intervertebral discs is called fibro cartilage.
Structure :
Fibro cartilage consists of chondrocytes dispersed among bundles of type 1 collagen fibers.
Chondrocytes are present in lacunae (cavity).
The arrangement of cells is different from all other type of cartilages.
Chondrocytes are arranged in parallel rows of 2, 4 or 6 cells.
These rows of cells are called isogenous cell groups.
Chemical Compounds Present :
Proteoglycans rich in sulphated glucosaminoglycans especially
Chondroiton sulphate
Dermatan sulphate
Stain :
Due to the abundance of collagen type 1 fibers , the matrix of fibrocartilage stains intensely acidophilic/eosinophilic. (since collagen is basic in nature)
Stained by EOSIN which is pink in color.
Chondrocytes are stained in purple usually by HEMATOXYLIN and looks purple in color due to acidic nature of large centeral nucleus present.
Occurrence in body :
Intervertebral disc
Disc of pubic symphysis
Menisci of knee joint
Sternoclavicular joint
Temporomandibular joint
Ligamentum tere
Labrum glenoidale
Labrum acetabulare
Fibrocartilage is also found at places where tendons and ligaments attach to bones.
Disorders:
Degeneration of fibrocartilage is seen in degenerative disc disease.
A fibrocartilaginous embolism (FCE) is an unusual cause of spinal cord and cerebral ischemia (insufficient bloodsupply). Symptoms may include sudden, severe pain in the neck and/or back; progressive weakening reduced sensation and paralysis. It may be caused by the blocking of an artery interrupting vascular supply.
A herniated disk is a disk that ruptures. This allows the jelly-like center of the disk to leak, irritating the nearby nerves. This can cause sciatica or back pain.
References:
http://www.nlm.nih.gov/medlineplus/herniateddisk.html
http://www.ncbi.nlm.nih.gov/pubmed/3289246
histology by laiq hussaain
Lecture 2 (anatomical and histological of bone )Ayub Abdi
The document summarizes the gross anatomy and microstructure of bone. It describes the parts of long bones including the diaphysis, epiphyses, and growth plates. It explains the differences between compact and spongy bone and their histological features. It also outlines the four main types of bone cells - osteoblasts, osteocytes, osteoclasts, and osteogenic cells - and their functions in bone formation and resorption.
The skeletal system is composed of bones and associated tissues that perform several essential functions:
1. Support - Bones provide structural support for the body and protection for internal organs.
2. Movement - Skeletal muscles use bones as levers to enable movement of the body.
3. Mineral storage - Bones store minerals like calcium and phosphorus.
There are over 200 bones in the human body that are classified as long, short, flat, or irregular. Bones are living tissues composed of cells like osteoblasts, osteocytes, and osteoclasts embedded in an organic bone matrix and inorganic minerals. Compact bone forms the dense outer layer while spongy bone composes the inner layer. Long bones have
Bone is a complex living tissue that provides structure, protection, and support. There are several types of bone tissue - cortical bone is dense and hard, forming the outer shell, while cancellous bone is spongy and light. Bones also contain bone marrow, which produces blood cells. Bones are made of an organic collagen matrix and inorganic hydroxyapatite crystals. They contain various bone cells that maintain the balance between bone formation and resorption. Bones come in different shapes suited to their functions, including long bones in the arms and legs, flat bones in the skull, and irregularly shaped bones.
Introduction, structure, functions and nutrition ofPramod Yspam
This document provides an overview of bone structure, functions, and nutrition. It discusses that bone is a mineralized connective tissue that provides structure and supports the body. It describes the different classifications of bones based on position, size, shape, and development. It explains the microscopic and cellular structure of bones, including compact and spongy bone, osteoblasts, osteocytes, osteoclasts, and the organic and inorganic components. Finally, it summarizes the functions of bone in providing structure, protection, movement, and hematopoiesis, as well as the blood supply, nerves, and lymphatic drainage of bones.
There are two types of bone tissue: compact bone which is dense and forms the outer layer, and spongy bone which is less dense and found in low stress areas. Bones are composed of osteocytes embedded in bone matrix, as well as osteoblasts which build bone, osteoclasts which resorb bone, and osteogenic cells which develop into osteoblasts. A long bone has a central shaft made of compact bone surrounding marrow, expanded ends made of inner spongy and outer compact bone lined with marrow, and growth plates between the shaft and ends.
There are two types of bone tissue: compact bone which is dense and forms the outer layer, and spongy bone which is less dense and found in low stress areas. Bones are composed of osteocytes embedded in bone matrix, as well as osteoblasts which build bone, osteoclasts which resorb bone, and osteogenic cells which develop into osteoblasts. A long bone has a central shaft made of compact bone surrounding marrow, expanded ends made of inner spongy and outer compact bone lined with marrow, and growth plates between the shaft and ends.
There are four main types of bones: long bones, short bones, flat bones, and irregular bones. Long bones have a shaft and two articulating ends, examples being the femur and humerus. Short bones are cube-shaped like wrist and ankle bones. Flat bones are broad and thin, found in the skull, shoulder blades, ribs, and sternum. Irregular bones come in various shapes and sizes, like the patella. Bones are made up of cells, fibers, and extracellular matrix. They provide structure, protection, movement, mineral storage, and blood cell formation to the body. Bone formation occurs through two processes - intramembranous ossification which forms flat bones, and endochondral oss
Fibrous joints are held together by connective tissue with no cavity present, and are either slightly mobile or immobile. Synovial joints contain synovial fluid and are freely movable, consisting of hyaline cartilage covering bone ends, a synovial membrane surrounding the joint cavity, and a fibrous capsule made of ligaments. Synovial joints allow for gliding, hinge, pivot, condyloid, saddle, and ball-and-socket movements. Long bones have a shaft and two expanded ends, short bones are any shape, flat bones resemble shallow plates, and irregular bones have completely irregular shapes.
There are two types of bone tissue: compact bone and spongy bone. Compact bone is dense and forms the outer protective layer, while spongy bone is less dense and found in low-stress areas. Bones are composed of osteocytes, osteoblasts, osteoclasts, and osteogenic cells which build, maintain, and remodel the bone tissue. Typical bone structure includes a diaphysis shaft surrounded by compact bone, epiphyses at the ends composed of inner spongy bone and outer compact bone, and metaphyses of cartilage between.
The skeletal system is composed of bones and associated tissues that provide structure, protection, movement, and mineral storage. Bones are living tissues composed of cells, collagen fibers, and minerals. There are four types of bones - long, short, flat, and irregular - with different structures adapted to their functions. Bones develop through intramembranous or endochondral ossification and are remodeled throughout life by bone cells.
The skeletal system has three main functions: providing structure and shape to the body, protecting vital organs, and allowing for bodily movement. It is made up of 206 bones that form the axial skeleton (skull, vertebrae, ribs, sternum) and appendicular skeleton (limbs and girdles). Bones are living tissues composed of compact bone, spongy bone, bone marrow, and various bone cells. They provide structure through their interaction with muscles, tendons, and ligaments at joints like the ball-and-socket hip. The skeletal system also plays roles in blood cell production and mineral storage.
This document summarizes key aspects of bone pathology. It identifies the main functions of bone tissue as support, protection, movement, mineral homeostasis, hematopoiesis, and storage. It describes the different shapes of bones and provides details on bone anatomy including diaphysis, epiphysis, growth plate, metaphysis, articular cartilage, periosteum, medullary cavity, endosteum, and blood and nerve supply. It explains the structure of compact and spongy bone, osteons, bone cells, and bone formation through intramembranous and endochondral ossification.
Osteology, derived from the from Greek ὀστέον (ostéon) 'bones', and λόγος (logos) 'study', is the scientific study of bones, practised by osteologists. A subdiscipline of anatomy, anthropology, and paleontology, osteology is the detailed study of the structure of bones, skeletal elements, teeth, microbone morphology, function, disease, pathology, the process of ossification (from cartilaginous molds), and the resistance and hardness of bones (biophysics).[1]
Osteologists frequently work in the public and private sector as consultants for museums, scientists for research laboratories, scientists for medical investigations and/or for companies producing osteological reproductions in an academic context.
Osteology and osteologists should not be confused with osteopathy and its practitioners, osteopaths.
This document provides an overview of bone anatomy and physiology. It defines bone, describes its various functions, and classifications including by position, shape, development, and structure. The document discusses the composition of bone, including its organic and inorganic components. It describes the anatomy of bone including its blood and nerve supply. Finally, it provides details on the histology of bone, the different cell types involved in bone formation and resorption, and the processes of ossification and bone remodeling throughout life.
Bones and its structure in detail with two different form of bone formationbhartisharma175
It consist of detail content about different types of bone cells, two different type of bone formation and structure of long bone. easy to understand for students. language is simple.
Bones provide structure, protect organs, allow movement, and store minerals. There are several bone types classified by shape. Long bones have a shaft and two ends, while short, flat, and irregular bones vary in shape. Bone tissue contains cells, water, collagen fibers, and minerals. Growth and remodeling is regulated by hormones and nutrients. Bones develop from cartilage templates in a multi-step process beginning before birth and continuing into early adulthood.
Bone is a connective tissue composed of cells and fibers embedded in a mineralized substance. It provides structural support and protection for the body. Bone tissue contains osteoblasts that form new bone, osteocytes embedded in the bone matrix, and osteoclasts that resorb bone. The bone matrix is made up of collagen fibers mineralized with hydroxyapatite crystals. Microscopically, bone is composed of concentric lamellae that form osteons in compact bone or a trabecular structure in spongy bone.
This document discusses skeletal physiology and contains sections on bone types, typical long bone structure, bone cells, homeostatic functions, bone development, bone healing, comparing bone and cartilage types, cartilage mechanisms, joint classification, and synovial joints. It provides detailed descriptions of bone anatomy and physiology, the roles of bones and cartilage, and how bones develop, break down, and heal. The information is presented through labeled sections and subsections explaining different skeletal structures and processes.
Bone is a living tissue that provides structure, protection, and movement. There are two types of bone formation: intramembranous, where bone forms within connective tissue, and endochondral, where bone replaces cartilage. Bones are composed of cells, organic components like collagen, and inorganic minerals. Bone tissue is continuously remodeled through the actions of osteoblasts which form bone and osteoclasts which resorb bone. Bones adapt and change their structure in response to mechanical stresses through Wolff's law.
The document summarizes the skeletal system, including its main components, functions, classification of bones, bone structure, development and growth. It discusses the two divisions of the skeleton - axial and appendicular. It also describes the different types of joints, their classification and movements allowed. The skeletal system provides structure and support to the body, protects internal organs, allows movement, stores minerals and enables blood cell formation. It consists of bones organized into an internal axial skeleton and external appendages.
हिंदी वर्णमाला पीपीटी, hindi alphabet PPT presentation, hindi varnamala PPT, Hindi Varnamala pdf, हिंदी स्वर, हिंदी व्यंजन, sikhiye hindi varnmala, dr. mulla adam ali, hindi language and literature, hindi alphabet with drawing, hindi alphabet pdf, hindi varnamala for childrens, hindi language, hindi varnamala practice for kids, https://www.drmullaadamali.com
Reimagining Your Library Space: How to Increase the Vibes in Your Library No ...Diana Rendina
Librarians are leading the way in creating future-ready citizens – now we need to update our spaces to match. In this session, attendees will get inspiration for transforming their library spaces. You’ll learn how to survey students and patrons, create a focus group, and use design thinking to brainstorm ideas for your space. We’ll discuss budget friendly ways to change your space as well as how to find funding. No matter where you’re at, you’ll find ideas for reimagining your space in this session.
Walmart Business+ and Spark Good for Nonprofits.pdfTechSoup
"Learn about all the ways Walmart supports nonprofit organizations.
You will hear from Liz Willett, the Head of Nonprofits, and hear about what Walmart is doing to help nonprofits, including Walmart Business and Spark Good. Walmart Business+ is a new offer for nonprofits that offers discounts and also streamlines nonprofits order and expense tracking, saving time and money.
The webinar may also give some examples on how nonprofits can best leverage Walmart Business+.
The event will cover the following::
Walmart Business + (https://business.walmart.com/plus) is a new shopping experience for nonprofits, schools, and local business customers that connects an exclusive online shopping experience to stores. Benefits include free delivery and shipping, a 'Spend Analytics” feature, special discounts, deals and tax-exempt shopping.
Special TechSoup offer for a free 180 days membership, and up to $150 in discounts on eligible orders.
Spark Good (walmart.com/sparkgood) is a charitable platform that enables nonprofits to receive donations directly from customers and associates.
Answers about how you can do more with Walmart!"
Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
LAND USE LAND COVER AND NDVI OF MIRZAPUR DISTRICT, UPRAHUL
This Dissertation explores the particular circumstances of Mirzapur, a region located in the
core of India. Mirzapur, with its varied terrains and abundant biodiversity, offers an optimal
environment for investigating the changes in vegetation cover dynamics. Our study utilizes
advanced technologies such as GIS (Geographic Information Systems) and Remote sensing to
analyze the transformations that have taken place over the course of a decade.
The complex relationship between human activities and the environment has been the focus
of extensive research and worry. As the global community grapples with swift urbanization,
population expansion, and economic progress, the effects on natural ecosystems are becoming
more evident. A crucial element of this impact is the alteration of vegetation cover, which plays a
significant role in maintaining the ecological equilibrium of our planet.Land serves as the foundation for all human activities and provides the necessary materials for
these activities. As the most crucial natural resource, its utilization by humans results in different
'Land uses,' which are determined by both human activities and the physical characteristics of the
land.
The utilization of land is impacted by human needs and environmental factors. In countries
like India, rapid population growth and the emphasis on extensive resource exploitation can lead
to significant land degradation, adversely affecting the region's land cover.
Therefore, human intervention has significantly influenced land use patterns over many
centuries, evolving its structure over time and space. In the present era, these changes have
accelerated due to factors such as agriculture and urbanization. Information regarding land use and
cover is essential for various planning and management tasks related to the Earth's surface,
providing crucial environmental data for scientific, resource management, policy purposes, and
diverse human activities.
Accurate understanding of land use and cover is imperative for the development planning
of any area. Consequently, a wide range of professionals, including earth system scientists, land
and water managers, and urban planners, are interested in obtaining data on land use and cover
changes, conversion trends, and other related patterns. The spatial dimensions of land use and
cover support policymakers and scientists in making well-informed decisions, as alterations in
these patterns indicate shifts in economic and social conditions. Monitoring such changes with the
help of Advanced technologies like Remote Sensing and Geographic Information Systems is
crucial for coordinated efforts across different administrative levels. Advanced technologies like
Remote Sensing and Geographic Information Systems
9
Changes in vegetation cover refer to variations in the distribution, composition, and overall
structure of plant communities across different temporal and spatial scales. These changes can
occur natural.
Main Java[All of the Base Concepts}.docxadhitya5119
This is part 1 of my Java Learning Journey. This Contains Custom methods, classes, constructors, packages, multithreading , try- catch block, finally block and more.
This presentation was provided by Steph Pollock of The American Psychological Association’s Journals Program, and Damita Snow, of The American Society of Civil Engineers (ASCE), for the initial session of NISO's 2024 Training Series "DEIA in the Scholarly Landscape." Session One: 'Setting Expectations: a DEIA Primer,' was held June 6, 2024.
2. 1. Classify the different types of bones of the human body
2. Describe the macro and microstructure of bones
3. Describe the biomechanical properties of cancellous and
cortical bones
4. Discuss the differences between cancellous and cortical bones
5. Describe the orientation of the human body and bones
6. Describe the functions of bones
Learning Outcomes
3. OSTEOLOGY
Study of Bones
is
Bone is a kind of mineralized connective tissue
The skeletal system is composed of the bones, cartilages, and joints that form the internal framework
4. Functions of boneFunctions of bone
• Support (Provide a framework for the human body)
• Movement (Provide leverage for movements)
• Protection (Protection of organs)
• Mineral storage
• Blood cell formation and energy storage
• Energy metabolism
5. Bone TissueBone Tissue
• Bone tissue consists of cells separated by an
extracellular matrix. Unlike other connective tissues,
bone has both organic and inorganic components.
• The organic components are the cells, fibers, and
ground substance.
• The inorganic components are the mineral salts that
invade the bony matrix, making bone tissue hard.
• Bone does contains a small amount of tissue fluid,
although bone contains less water than other
connective tissues.
6. Bone Tissue –Bone Tissue –
Extracellular matrixExtracellular matrix
• The organic components of bone tissue account for
35% of the tissue mass.
o These organic substances, particularly collagen, contribute the flexibility
and tensile strength that allow bone to resist stretching and twisting
• Balance of bone tissue, 65% by mass, consists of
inorganic hydroxyapatites, or mineral salts, primarily
calcium phosphate.
o These mineral salts are present as tiny crystals that lie in and around the
collagen fibrils in the extracellular matrix.
o The crystals pack tightly, providing bone with its exceptional hardness,
which enables it to resist compression.
o These mineral salts also explain how bones can endure for hundreds of
millions of years, providing information on the sizes, shapes, lifestyles, and
even some of the diseases (for example, arthritis) of ancient vertebrates.
7. • Three types of cells in bone tissue produce or maintain
the tissue: osteogenic cells, osteoblasts, and osteocytes
• Osteogenic cells are stem cells that differentiate into
bone-forming osteoblasts
• Osteoblasts are cells that actively produce and secrete
the organic components of the bone matrix: the ground
substance and the collagen fibers. This bone matrix
secreted by osteoblasts is called osteoid. Within a week,
inorganic calcium salts crystallize within the osteoid.
Once osteoblasts are completely surrounded by bone
matrix and are no longer producing new osteoid, they
are called osteocytes.
• Osteocytes function to keep the bone matrix healthy
Bone Tissue – CellsBone Tissue – Cells
8. • The cells responsible for the resorption of bone are
the fourth type of cell found within bone tissue,
osteoclasts.
• Osteoclasts are derived from a lineage of white
blood cells. These multinucleated cells break down
bone by secreting hydrochloric acid, which
dissolves the mineral component of the matrix, and
lysosomal enzymes, which digest the organic
components.
11. Structure of a typical long boneStructure of a typical long bone
• Diaphysis and
Epiphyses
• Blood Vessels
• The Medullary
Cavity
• Membranes
• Diaphysis and Epiphyses:
o The tubular diaphysis, or shaft, forms the long axis of
a long bone
o Epiphyses are the bone ends. The joint surface of
each epiphysis is covered with a thin layer of hyaline
cartilage called the articular cartilage.
o Between the diaphysis and each epiphysis of an
adult long bone is an epiphyseal line. This line is a
remnant of the epiphyseal plate, a disc of hyaline
cartilage that grows during childhood to lengthen
the bone.
12. • Blood Vessels - bones are well
vascularized.
o Between 3% and 11% of the blood in the body is in the
skeleton.
o The main vessels serving the diaphysis are a nutrient
artery and a nutrient vein.
o Together these run through a hole in the wall of the
diaphysis, the nutrient foramen. The nutrient artery runs
inward to supply the bone marrow and the spongy
bone.
o Branches then extend outward to supply the compact
bone.
o Several epiphyseal arteries and veins serve each
epiphysis in the same way.
• The Medullary Cavity
o The interior of all bones consists largely of spongy bone.
o The very center of the diaphysis of long bones contains
no bone tissue at all and is called the medullary cavity
or marrow cavity, filled with yellow bone marrow.
o The spaces between the trabeculae of spongy bone are
also filled with marrow.
13. • Membranes
o A connective tissue membrane covering entire surface of
bone except epiphysis called the periosteum.
o This periosteal membrane has two sublayers:
• a superficial layer of dense irregular connective tissue,
which resists tension placed on a bone during bending,
• deep layer that abuts the compact bone. This deep
layer is osteogenic, containing bone-depositing cells
(osteoblasts) and bonedestroying cells (osteoclasts).
• These cells remodel bone surfaces throughout our lives .
• The osteogenic cells of the deep layer of the
periosteum are indistinguishable from the fibroblasts
within this layer.
o The periosteum is richly supplied with nerves and blood
vessels, which is why broken bones are painful and bleed
profusely.
o The periosteum provides insertion points for tendons and
ligaments that attach to a bone. At these points, the
perforating fibers are exceptionally dense. Whereas
periosteum covers the external surface of bones, internal
bone surfaces are covered by a much thinner connective
tissue membrane called endosteum. Specifically,
endosteum covers the trabeculae of spongy bone, it also
lines the central canals of osteons. Like periosteum,
endosteum is osteogenic, containing both osteoblasts and
osteoclasts.
14.
15. • Structure of Short,
Irregular, and Flat
Bones
o have much the same
composition as long bones:
periosteum-covered
compact bone externally
and endosteum-covered
spongy bone internally.
o these bones are not
cylindrical, they have no
diaphysis. They contain
bone marrow (between the
trabeculae of their spongy
bone), but no marrow cavity
is present
o A typical flat bone of the
skull.
16. Bone Design and Stress
•Bones are subjected to compression as
weight bears down on them or as muscles
pull on them.
•The loading usually is applied off center,
however, and threatens to bend the bone
• Bending compresses the bone on one
side and stretches it (subjects it to tension)
on the other.
•Both compression and tension are
greatest at the external bone surfaces.
•The spongy bone and marrow cavities
lighten the heavy skeleton and provide
room for the bone marrow.
•The surfaces of bones also reflect the
stresses that are applied to the bone. The
superficial surfaces have distinct bone
markings
18. Internal macrostructure of long bone
Epiphysis: Cancellous bone
Diaphysis: Cortical bone/compact
bone
Medullary Cavity: bone marrow
for formation of red blood cell
Covering of the bone is periosteum
Perforation at the surface of the bone:
Foramen for blood vessels
19. Irregular Bones and short bones
Cancellous Bone
Outer layer is cortical
bone
Cancellous / Spongy bone
20. Microscopic structure ofMicroscopic structure of
compact bonecompact bone
Osteon, or Haversian system –
•Osteons are long, cylindrical structures oriented
parallel to the long axis of the bone and to the main
compression stresses.
•Functionally, osteons can be viewed as miniature
weight-bearing pillars.
•Structurally, an osteon is a group of concentric tubes
resembling the rings of a tree trunk in
•cross section.
•Each of the tubes is a lamella, a layer of bone matrix
in which the collagen fibers and mineral crystals align
and run in a single direction.
21.
22. • In each osteon runs a canal called the central canal, or
Haversian canal lined by endoteum
• Central canal contains its own blood vessels, which supply
nutrients to the bone cells of the osteon, and its own nerve
fibers.
• Perforating canals, also called Volkmann’s canals, lie at right
angles to the central canals and connect the blood and
nerve supply of the periosteum to that of the central canals
and the marrow cavity.
• The mature bone cells, the osteocytes, are spider-shaped,
their bodies occupy small cavities in the solid matrix called
lacunae, and their “spider legs”occupy thin tubes called
canaliculi.
• These “little canals” run through the matrix, connecting
neighboring lacunae to one another and to the nearest
capillaries, such as those in the central canals.
23. • Lying between the osteons are
groups of incomplete lamellae
called interstitial
• These are simply the remains of
old osteons that have been cut
through by bone remodeling.
• Additionally, circumferential
lamellae occur in the external
and internal surfaces of the
layer of compact bone; each
of these lamellae extends
around the entire
circumference of diaphysis
• Functioning like an osteon but
on a much larger scale, the
circumferential lamellae
effectively resist twisting of the
entire long bone.
24. Macroscopic structure ofMacroscopic structure of
spongy bonespongy bone
• Each trabecula contains
several layers of lamellae and
osteocytes but is too small to
contain osteons or vessels of
its own. The osteocytes
receive their nutrients from
capillaries in the endosteum
surrounding the trabecula via
connections through the
canaliculi.
26. Lateral
(directed away from midline
of the human body)
Superior / cranial
(direction upwards towards head)
Mid line
Inferior / caudal
(directed downawards towards
the legs)
Medial
(directed towards the midline
of the human body)
27. midline
Superior / cranial
(direction upwards towards head)
Lateral
(directed away from midline
of the human body)
Medial
(directed towards the midline
of the human body)
Inferior / caudal
(directed downawards towards
the legs)
32. ReferencesReferences
• Drake RL., Vogl AW. & Mitchell AWM (2009)
Gray's Anatomy for Students: With STUDENT CONSULT Online Access
. Churchill Livingstone (2nd.edn)
• Levangie PK & Norkin C. (2005) Joint Structure and Function: A
comprehensive analysis (4th edn). FA Davis Co.
• Nordin M. & Frankel VH (2012) Basic Biomechanics of the
Musculoskeletal System (4th ed.) Lippincott Williams & Wilkins.
• Palastanga N., Soames R. & Field D (2006) Anatomy and Human
Movement: Structure and Function (Physiotherapy Essentials.
Butterworth Heinnemann (5th edn.)
• Tortora GJ. & Derrickson B. (2011) Principles of Anatomy and
Physiology (13th edn.) . John Wiley and Sons.
Editor's Notes
1. Support. Bones provide a hard framework that supports the weight of the body. For example, the bones of the legs are pillars that support the trunk of the body in the standing person.
2. Movement. Skeletal muscles attach to the bones by tendons and use the bones as levers to move the body and its parts. As a result, humans can walk, grasp objects, and move the rib cage to breathe. The arrangement of the bones and the structure of the joints determine the types of movement that are possible. Support and movement are mutually dependent functions: The supportive framework is necessary for movement, and the skeletal muscles contribute significantly to the support of body weight.
3. Protection. The bones of the skull form a protective case for the brain. The vertebrae surround the spinal cord, and the rib cage helps protect the organs of the thorax.
4. Mineral storage. Bone serves as a reservoir for minerals, the most important of which are calcium and phosphate. The stored minerals are released into the bloodstream as ions for distribution to all parts of the body as needed.
5. Blood cell formation and energy storage. Bones contain red and yellow bone marrow. Red marrow makes the blood cells, and yellow marrow is a site of fat storage, with little or no role in blood cell formation. Red bone marrow and the production of blood cells.
6. Energy metabolism. The role of bone cells in regulating energy metabolism has just recently been identified. Bone-producing cells, osteoblasts ,secrete a hormone that influences blood sugar regulation. This hormone, osteocalcin, stimulates pancreatic secretions that reduce blood sugar levels (insulin). Osteocalcin also influences fat cells, causing them to store less fat and to secrete a hormone that increases the insulin sensitivity of cells. These results have clinical implications for the treatment of metabolic disorders related to blood sugar regulation, such as type 2 diabetes.
At the ends of the epiphyses articular cartilage occurs
During periods of bone growth or deposition, the osteogenic cells differentiate into osteoblasts. These osteoblasts produce the layers of bone tissue that encircle the perimeter of the bone, the circumferential lamellae.
The vessels that supply the periosteum are branches from the nutrient and epiphyseal vessels. The periosteum is secured to the underlying bone by perforating fibers (Sharpey’s fibers), thick bundles of collagen that run from the periosteum into the bone matrix.
To resist these maximal stresses, the strong, compact bone tissue occurs in the external portion of the bone. Internal to this region, however, tension and compression forces tend to cancel each other out, resulting in less overall stress. Thus, compact bone is not found in the bone interiors; spongy bone is sufficient.
Because no stress occurs at the bone’s center, the lack of bone tissue in the central medullary cavity does not impair the strength of long bones. In fact, a hollow cylinder is stronger than a solid rod of equal weight, thus this design is efficient from a biological as well as a mechanical perspective.