Presentation on theme: "By Susan Song, Julienne Kim and Kelsey Osborn"— Presentation transcript:
1By Susan Song, Julienne Kim and Kelsey Osborn The skeletal systemBy Susan Song, Julienne Kim and Kelsey Osborn
2BONE FUNCTION: Support and Protection Give shape and provide protection to head, face, thorax, and limbs Structural support for heart, lungs and marrow Protection for brain, uterus, and other internal organs Attachment sites for muscles allowing movement of limbs
3BONE FUNCTION: Body Movement Movement is possible through of the attachment of bones to muscles. (Tendons)Bones and muscles interact as mechanical devices called levers.4 basic components of levers: 1) rod or bar2) pivot point ) object moving against resistance4) force supplying energyMcGrallHill Textbook
4BONE FUNCTION: Blood Cell Formation 3 groups of blood cells: red blood cells, white blood cells, and plateletsAlso called hematopoiesisBegins in the yolk sac, later occurs in the liver and spleen, and finally in bone marrowMarrow: soft mass of connective tissue found within medullary cavities of long bones, spongy bone, and central canals of compact bone tissue2 kinds of bone marrow: Red marrow and yellow marrow
5Continued…Red marrow: formation of red blood cells, white blood cells and platelets.In infants, red marrow occupies the cavities of bonesYellow marrow: stores fat. Is not active in blood formationHowever, if needed, can become red marrow, then reverts back to yellow marrow
6BONE FUNCTION: Storage of Inorganic Salts The extracellular matrix of bone tissue is rich in calcium saltsVital Metabolic processes require calciumWhen blood is low in calcium, osteoclasts break down bone tissue, which releases calcium salts into the bloodHigh blood calcium activates osteoclasts and causes the release of calcitonin, which stimulates osteoblasts to form bone tissue.Excess calcium is stored in the extracellular matrix
7Bones Bone tissue is a type of dense connective tissue. Come in a variety of shapes and have a complex internal and external structureLightweight, yet strong and hardRigid and has a honeycomb-like, three-dimensional internal structure.Includes marrow, endosteum and periosteum, nerves, and blood vesselsThere are 206 bones in the adult human body and 270 in an infant.
8Ligaments Connect bone to another bone Allow most joints to move help control their range of motionStabilize them so that the bones move in proper alignmentCollagen makes up the tissue in most ligaments.Collagen fibers allow to stretch significantly when they move, such as when the elbow is bent or straightened.
9TendonsTough band of fibrous connective tissue that usually connect muscle to boneCapable of withstanding great tension.Similar to ligaments and fasciae as they are all made of collagen but ligaments join one bone to another bone, and fasciae connect muscles to other muscles.Tendons and muscles work together
10CartilageFlexible connective tissue found in many areas in the body like the rib cage, the ear, the nose.Provide support, frameworks, and attachmentsProtect underlying tissuesForm structural models for developing bonesNot as hard and rigid as bone but is stiffer and less flexible than muscle.3 types: elastic cartilage, hyaline cartilage and fibrocartilageDo not contain blood vessels and as a result, heals very slowly./about/wayne.schaefer/TissuesPage.htm/2009/10/fibrocartilage.html
11Bone Development and Growth The skeletal systems begins to grow during prenatal developmentContinues to grow into adulthoodForm by replacing existing connective tissues2 types of bone formation: Intramembranous and endochondral
12Bone Development and Growth: Intramembranous Ossification Formation of flat bones like the skull Connective tissue forms in sheets at sites of future bonesHighly invested with blood vessels. The future bones are first formed as connective tissue membranes.Osteoblasts migrate to the membranes and deposit bony matrix around themselves.As a result, spongy bone tissue forms in all directions within the membrane layersPeriosteum: cells of the membranous tissues that lie outside the developing boneOsteoblasts lie within the periosteum and form compact bone around spongy bone
13Endochondral Ossification: Replacement of hyaline cartilage with bony tissue.Most of the bones of the skeleton are formed in this manner.Primary Ossification CenterSecondary Ossification CenterFuture bones first form as hyaline cartilage models.3rd month after conception: the perichondrium that surrounds the hyaline cartilage models fills with blood vessels and osteoblasts and changes into a periosteum.The osteoblasts form a collar of compact bone around the diaphysis. Cartilage in the center of the diaphysis begins to disintegrate.Osteoblasts penetrate the disintegrating cartilage and replace it with spongy bone.Continues from the center toward the ends of the bones.After spongy bone is formed in the diaphysis, osteoclasts break down the newly formed bone to open up the medullary cavity.As the developing bone increases in length, cartilage continues to disintegrateWhen secondary ossification is complete, the hyaline cartilage is totally replaced by bone but a region of hyaline cartilage remains over the surface of the epiphysis as articular cartilage
20Joints Fibrous Cartilaginous Synovial Lie closely between one another Thin layer of dense conn. tissueI.e. sutures on skull bonesCartilaginousHyaline cartilage or fibrocartilageSeparate the vertebral columnSynovialMostly of all joinsAllows free movementComplex structures
21Pivot Gliding Hinge Six Synovial Joints Condyloid saddle Ball-and-socketCondyloidPivotHingeGliding
31Osteoporosis=porous bone Thinning and weakening of the boneMore common to womenLow bone density and low dietary sodium intakeHips, wrists, and spineConsidered a ‘silent disease’Can be prevented or treated with a healthy lifestyle; correct diet, exercise, and medications such as bisphonatesOsteoporosis=porous bone
32Osteogenesis Imperfecta Congenital DiseaseMore common within shorter statureBones become weakerDamages in the gene for type 1 collagenBlue tint to the whites of the eye, hearing losses, and multiple fracturesNo definite cure
33Bone Tumor Abnormal growth of bones Genetics, radiation, injury Symptoms: Pain (night) and fracturesTreated like most cancers
34Work Cited"Bone tumor - PubMed Health." National Center for Biotechnology Information. N.p., n.d. Web. 26 Feb <http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH /> "Osteogenesis imperfecta - PubMed Health." National Center for Biotechnology Information. Web. 23 Feb <http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH > "NIHSeniorHealth: Osteoporosis - What Is Osteoporosis?." NIHSeniorHealth Home Page. N.p., n.d. Web. 24 Feb <http://nihseniorhealth.gov/osteoporosis/whatisosteoporosis/01.html> Shier, David, Jackie Butler, and Ricki Lewis. Hole's essentials of human anatomy and physiology. 9th ed. Boston: McGraw-Hill, Print.