What kind of tissue is responsible for this quality of toughness




















The cornea is the tissue that covers the pupil and iris. It is what a contact lens covers on the eyeball. The sclera is the white of the eye. It is called the cornea. Meristematic tissue is responsible for plant's unceasing growth. It is apical as well as intercallary. The apical meristem is responsible for longitudenal growth.

The dermal tissue structures responsible for fingerprints are dermal papillae. They are tiny extensions of the dermis into the epidermis.

Nervous Tissue. This tissue is called dermal tissue. It can also be called a cuticle. The tissue that is responsible for a plant's unceasing growth is the meristematic tissue. It is also known as growing tip and is located in the buds. It contains undifferentiated cells that promote growth. Xylem is responsible for water transportation.

It is a complex tissue. Fibroblasts are the most common resident cells in ordinary connective tissue. Fibroblasts are responsible for secreting collagen and other elements of the extracellular matrix of connective tissue.

Smooth Muscle Tissue. What type of tissue is responsible for contractions that account for movements of organs or the entire body. Log in. Add an answer. A tissue membrane is a thin layer or sheet of cells that covers the outside of the body for example, skin , the organs for example, pericardium , internal passageways that lead to the exterior of the body for example, abdominal mesenteries , and the lining of the moveable joint cavities.

There are two basic types of tissue membranes: connective tissue and epithelial membranes Figure 3. Figure 3. Tissue Membranes. The two broad categories of tissue membranes in the body are 1 connective tissue membranes, which include synovial membranes, and 2 epithelial membranes, which include mucous membranes, serous membranes, and the cutaneous membrane, in other words, the skin.

The connective tissue membrane is formed solely from connective tissue. These membranes encapsulate organs, such as the kidneys, and line our movable joints. A synovial membrane is a type of connective tissue membrane that lines the cavity of a freely movable joint. For example, synovial membranes surround the joints of the shoulder, elbow, and knee. Fibroblasts in the inner layer of the synovial membrane release hyaluronan into the joint cavity. The hyaluronan effectively traps available water to form the synovial fluid, a natural lubricant that enables the bones of a joint to move freely against one another without much friction.

This synovial fluid readily exchanges water and nutrients with blood, as do all body fluids. The epithelial membrane is composed of epithelium attached to a layer of connective tissue, for example, your skin. The mucous membrane is also a composite of connective and epithelial tissues. Sometimes called mucosae, these epithelial membranes line the body cavities and hollow passageways that open to the external environment, and include the digestive, respiratory, excretory, and reproductive tracts.

Mucous, produced by the epithelial exocrine glands, covers the epithelial layer. A serous membrane is an epithelial membrane composed of mesodermally derived epithelium called the mesothelium that is supported by connective tissue. These membranes line the coelomic cavities of the body, that is, those cavities that do not open to the outside, and they cover the organs located within those cavities. They are essentially membranous bags, with mesothelium lining the inside and connective tissue on the outside.

Serous fluid secreted by the cells of the thin squamous mesothelium lubricates the membrane and reduces abrasion and friction between organs. Basic material properties The material behavior of cortical bone is anisotropic. Open in a separate window. Figure 1. Table 1 Elastic, yield, and ultimate properties of human femoral cortical bone a. Viscoelasticity The effect of loading rate on strength and modulus is only moderate, as a six-order increase in the strain rate raises the modulus only by a factor of two and the strength by a factor of three 1.

Damage When cortical bone is loaded past the yield point, degradation of the material properties occurs Figure 1 b 3. Figure 2. Fracture and fatigue Fracture of cortical bone can occur from repetitive, subcritical loads fatigue failure or from applied loads that cause local stresses exceeding the strength of the tissue. Figure 3. Failure under multiaxial loading Cortical bone can be subjected to multiaxial loading conditions in the body, especially during traumatic events such as a fall.

Micro- and nanoscale properties of cortical tissue The mechanical properties described above pertain to specimens of cortical bone whose dimensions are on the order of several millimeters or centimeters. Influence of porosity and tissue composition on the mechanical properties of cortical bone Early research on the microstructural and compositional factors that control the mechanical properties of cortical bone focused largely on porosity and mineralization. Micro- and nanomechanical modeling of cortical bone Micro- and nanomechanical models can improve our understanding of the structure—function relationships at multiple length scales in cortical bone.

Effects of aging and disease on the mechanical properties of cortical bone Age-related changes in the mechanical properties of cortical bone have been attributed to increased porosity 45 , hypermineralization 64 , microdamage accumulation 23 , increased concentration of AGEs 65 , and decreased quantity of noncollagenous proteins Mechanical Behavior of Trabecular Bone Trabecular bone—also referred to as cancellous or spongy bone—can be viewed at the apparent level i.

Basic material properties As with cortical bone, the strength of trabecular bone is greater in compression than tension, and is lowest in shear, although these differences decrease with decreasing apparent density Heterogeneity in mechanical properties due to density and architecture Several different measures of density are used in biomechanical studies of trabecular bone.

Figure 4. Yield strain Yield strain is a notable exception to the above-mentioned mechanical anisotropy and density dependence of trabecular bone. Viscoelasticity The compressive modulus and compressive strength are proportional to the strain rate raised to the power of 0.

Damage The large reduction in apparent modulus that occurs with overloading Figure 2 b results from damage within the trabeculae, namely microscopic cracking as opposed to overt fracture of individual trabeculae Fracture and fatigue The fracture toughness of trabecular bone has not been studied extensively, because the porous and spatially heterogeneous microstructure presents a significant challenge for meeting the requirements of a fracture-toughness test.

Yield and failure under multiaxial loading Because complex loading conditions can exist in vivo and nonhabitual events such as falls or accidents can induce off-axis loads, a multiaxial failure criterion for trabecular bone is needed. Analytical modeling Seminal research in the development of analytical models for the mechanical behavior of trabecular bone considered this porous tissue a cellular solid Numerical modeling The advantages of analytical models in providing closed-form relationships for the mechanical properties of trabecular bone must be balanced against the errors in the model predictions that arise from oversimplifications of the trabecular architecture and tissue-level material properties.

Mechanical properties of trabecular tissue Trabecular tissue, which is the bony tissue that comprises individual trabeculae, is similar to cortical bone in both composition and material properties.

Effects of aging and disease on the mechanical behavior of trabecular bone The density and architecture of trabecular bone undergo profound changes with age. Figure 5. Loading of Whole Bones In Vivo and In Vitro A major challenge in the design of laboratory tests that seek to characterize clinically relevant mechanical behavior of a whole bone is to identify loading conditions that are physiologically representative. Role of Geometry in Whole-Bone Mechanical Behavior Principles of engineering mechanics stipulate that the axial stiffness, in either compression or tension, of a structure is proportional to the cross-sectional area, while the bending and torsional stiffnesses of beam-like structures such as diaphyses depend on how the material tissue is distributed around the axis of bending or twist.

Effect of Aging and Disease on the Mechanical Behavior of Whole Bones Cross-sectional geometry and other geometric features of whole bones exhibit marked changes with age. Figure 6. McElhaney JH. Dynamic response of bone and muscle tissue. J Appl Physiol. Microcracking damage and the fracture process in relation to strain rate in human cortical bone tensile failure. J Biomech. A damage model for nonlinear tensile behavior of cortical bone.

J Biomech Eng. Frost HM. Presence of microscopic cracks in vivo in bone. Henry Ford Hosp Bull. Martin RB. Fatigue microdamage as an essential element of bone mechanics and biology. Calcif Tissue Int. Varvani-Farahani A, Najmi H. A damage assessment model for cadaveric cortical bone subjected to fatigue cycles.

Int J Fatigue. Dilatational band formation in bone. The role of the lamellar interface during torsional yielding of human cortical bone.

Does microdamage accumulation affect the mechanical properties of bone? Non-destructive characterization of microdamage in cortical bone using low field pulsed NMR.

J Mech Behav Biomed Mater. Influence of microdamage on fracture toughness of the human femur and tibia. Age-related differences in post-yield damage in human cortical bone. Experiment and model. Mechanical and morphological effects of strain rate on fatigue of compact bone. Contribution, development and morphology of micro-cracking in cortical bone during crack propagation.

Fracture in human cortical bone: local fracture criteria and toughening mechanisms. Bonfield W, Datta PK. Fracture toughness of compact bone. Fracture resistance of human cortical bone across multiple length scales at physiological strain rates. Strain rate influence on human cortical bone toughness: a comparative study of four paired anatomical sites.

The fracture mechanics of human bone: influence of disease and treatment. BoneKEy Rep. Cyclic mechanical property degradation during fatigue loading of cortical bone. Effects of fatigue induced damage on the longitudinal fracture resistance of cortical bone.

J Mater Sci Mater Med. Compact bone fatigue damage—I. Residual strength and stiffness. Tensile fatigue in bone: Are cycles-, or time to failure, or both, important? J Theor Biol. Bone creep—fatigue damage accumulation. Sequential labelling of microdamage in bone using chelating agents. J Orthop Res. Contrast-enhanced microcomputed tomography of fatigue microdamage accumulation in human cortical bone.

Zysset PK, Curnier A. A 3D damage model for trabecular bone based on fabric tensors. George WT, Vashishth D. Susceptibility of aging human bone to mixed-mode fracture increases bone fragility.

Mixed-mode toughness of human cortical bone containing a longitudinal crack in far-field compression. Anisotropic yield behavior of bone under combined axial force and torque. A generalized anisotropic quadric yield criterion and its application to bone tissue at multiple length scales. Biomech Model Mechanobiol.

A multidimensional anisotropic strength criterion based on Kelvin modes. Int J Solids Struct. The torsional properties of single selected osteons.

Interfacial strength of cement lines in human cortical bones. Mech Chem Biosyst. Osteon interfacial strength and histomorphometry of equine cortical bone. Elastic properties of human cortical and trabecular lamellar bone measured by nanoindentation. Franzoso G, Zysset PK. Elastic anisotropy of human cortical bone secondary osteons measured by nanoindentation.

An application of nanoindentation technique to measure bone tissue lamellae properties. In situ micropillar compression reveals superior strength and ductility but an absence of damage in lamellar bone. Nat Mater. The nanocomposite nature of bone drives its strength and damage resistance. Microscopic assessment of bone toughness using scratch tests. Bone Rep. Stiffness of compact bone: effects of porosity and density. Variations in strength and structure of cancellous bone at the knee.

Ural A, Vashishth D. Effects of intracortical porosity on fracture toughness in aging human bone: a microCT-based cohesive finite element study. Age-related changes in the tensile properties of cortical bone: the relative importance of changes in porosity, mineralization and microstructure. J Bone Joint Surg. Fatigue microcracks that initiate fracture are located near elevated intracortical porosity but not elevated mineralization. Kovacs CS. The skeleton is a storehouse of mineral that is plundered during lactation and fully?

J Bone Miner Res. Atypical fracture with long-term bisphosphonate therapy is associated with altered cortical composition and reduced fracture resistance. Influence of nonenzymatic glycation on biomechanical properties of cortical bone. Boskey AL. Bone composition: relationship to bone fragility and antiosteoporotic drug effects.

Contributions of Raman spectroscopy to the understanding of bone strength. Towards the in vivo prediction of fragility fractures with Raman spectroscopy. J Raman Spectrosc. Jager I, Fratzl P. Mineralized collagen fibrils: a mechanical model with a staggered arrangement of mineral particles.

Biophys J. A new model to simulate the elastic properties of mineralized collagen fibril. Role of intrafibrillar collagen mineralization in defining the compressive properties of nascent bone. Modeling of stiffness and strength of bone at nanoscale. Bone mineral lies mainly outside collagen fibrils: predictions of a composite model for osternal bone.

Katz JL. Mineral-collagen interactions in elasticity of bone ultrastructure—a continuum micromechanics approach. Eur J Mech A. Specimen-specific multi-scale model for the anisotropic elastic constants of human cortical bone.

The estimated elastic constants for a single bone osteonal lamella. Determination of the heterogeneous anisotropic elastic properties of human femoral bone: from nanoscopic to organ scale.

Effect of porosity and mineral content on the elastic constants of cortical bone: a multiscale approach. The effects of ageing and changes in mineral content in degrading the toughness of human femora. Age-related changes in the collagen network and toughness of bone. Sroga GE, Vashishth D. Effects of bone matrix proteins on fracture and fragility in osteoporosis. Curr Osteoporos Rep. Effect of aging on the toughness of human cortical bone: evaluation by R-curves.

Aging of bone tissue: mechanical properties. J Bone Joint Surg Am. Effect of aging on the transverse toughness of human cortical bone: evaluation by R-curves. Effects of insulin therapy on porosity, non-enzymatic glycation and mechanical competence in the bone of rats with type 2 diabetes mellitus. The effect of osteoporosis treatments on fatigue properties of cortical bone tissue.

Bone microdamage: a clinical perspective. Osteoporos Int. Increasing duration of type 1 diabetes perturbs the strength—structure relationship and increases brittleness of bone. Advanced glycation endproducts and bone material properties in type 1 diabetic mice. How tough is brittle bone? Investigating osteogenesis imperfecta in mouse bone. Differences between the tensile and compressive strengths of bovine tibial trabecular bone depend on modulus.

Nonlinear behavior of trabecular bone at small strains. Mechanical behavior of human trabecular bone after overloading. Biomechanical consequences of an isolated overload on the human vertebral body. Dependence of yield strain of human trabecular bone on anatomic site. Whitehouse WJ. The quantitative morphology of anisotropic trabecular bone. J Microsc. Harrigan T, Mann R.

Characterization of microstructural anisotropy in orthotropic materials using a second rank tensor. J Mater Sci. Cowin SC.

The relationship between the elasticity tensor and the fabric tensor. Mech Mater. Inhomogeneity of human vertebral cancellous bone: systematic density and structure patterns inside the vertebral body. The mechanical properties of human tibial trabecular bone as a function of metaphyseal location.

Evaluation of orthogonal mechanical properties and density of human trabecular bone from the major metaphyseal regions with materials testing and computed tomography. Bone compressive strength: the influence of density and strain rate.

Trabecular bone modulus—density relationships depend on anatomic site. Biomechanical competence of vertebral trabecular bone in relation to ash density and age in normal individuals. Fabric and elastic principal directions of cancellous bone are closely related. J Elast. A global relationship between trabecular bone morphology and homogenized elastic properties.

Elastic anisotropy of trabecular bone in the elderly human vertebra. Uniaxial yield strains for bovine trabecular bone are isotropic and asymmetric.



0コメント

  • 1000 / 1000