Bone Function of Bone Movement Can change the position of body parts Protection Hard cases that enclose organs (brain) Support Anchor muscles Mineral.

BoneBoneFunction of BoneFunction of BoneMovementMovement Can change the position of body parts Can change the position of body partsProtection Protection Hard cases that enclose organs (brain) Hard cases that enclose organs (brain)Support Support Anchor muscles Anchor musclesMineral Storage Mineral Storage Stores phosphate, and calcium Stores phosphate, and calciumBlood cell formation Blood cell formation Bone marrow produces blood cells Bone marrow produces blood cells

BoneBoneBone is the most rigid type of connective tissueBone is the most rigid type of connective tissue

Living bone cells are called osteocytes, Living bone cells are called osteocytes, which are made from collagen and elastinwhich are made from collagen and elastin

Osteocytes, after being made, settle in the Osteocytes, after being made, settle in the open spaces (or cavities) in bone called lacunaeopen spaces (or cavities) in bone called lacunae

Compact BoneCompact Bone•Forms on the outside of bonesForms on the outside of bones•Densely packed with collagenDensely packed with collagen•Outside covering of the bone is called the periosteumOutside covering of the bone is called the periosteum•Compact bone is organized as thin concentric circles called a Compact bone is organized as thin concentric circles called a Haversian System (osteons)Haversian System (osteons)•The channels in the osteons are used for the connection of The channels in the osteons are used for the connection of blood vessels and nerves; they are called Haversian Canalsblood vessels and nerves; they are called Haversian Canals•Osteocytes are connected together by small protrusions called Osteocytes are connected together by small protrusions called canaliculicanaliculi

Osteocytes connected Osteocytes connected together by canaliculitogether by canaliculi

Canaliculi Canaliculi

Osteocyte Osteocyte

Spongy BoneSpongy BoneForms the interior portion of bonesForms the interior portion of bonesFlat lattice fuses together to form a hard interiorFlat lattice fuses together to form a hard interiorInside the spaces of spongy bone is red marrow and yellow Inside the spaces of spongy bone is red marrow and yellow marrowmarrowRed marrow Red marrow synthesizes red; white blood cells; especially in synthesizes red; white blood cells; especially in hip and sternumhip and sternumYellow marrow Yellow marrow synthesizes fat synthesizes fat

Development of BonesDevelopment of BonesCartilage serves as starting point of bone growth

Periosteum covers newly forming osteoblasts and osteocytes

The cartilage then begins to calcify

Each end of a bone is called an epiphysis

At the end of the epiphysis is the epiphyseal plate, which contributes to bone growth

The growth of the epiphyseal plate is controlled by growth hormone, which is released by the pituitary gland

Bone RemodelingBone RemodelingOver time calcium and phosphate are added and Over time calcium and phosphate are added and withdrawn from bone tissuewithdrawn from bone tissue

Osteoblasts deposit bone and osteoclasts Osteoblasts deposit bone and osteoclasts break it downbreak it down

Most bones are cartilaginous during development Most bones are cartilaginous during development

During development, bones grow from the During development, bones grow from the middle outmiddle out

In adulthood, bones grow from either endIn adulthood, bones grow from either end

Each growing end of the bones is called an Each growing end of the bones is called an ossification centerossification center

Calcium in BoneCalcium in BoneCalcium is needed for lots of physiological processes, Calcium is needed for lots of physiological processes, including muscle contraction and nerve including muscle contraction and nerve communicationcommunication

When calcium in blood decreases, parathyroid When calcium in blood decreases, parathyroid hormone stimulates osteoclasts to release enzymes hormone stimulates osteoclasts to release enzymes that remove calcium from bonethat remove calcium from bone

When there is an abundance of calcium in the blood, When there is an abundance of calcium in the blood, calcitonin stimulates osteoblasts to take in calcium calcitonin stimulates osteoblasts to take in calcium from the blood to synthesize new bonefrom the blood to synthesize new bone

Calcium in BoneCalcium in BoneRemodeling also occurs in Remodeling also occurs in response to exercise.response to exercise.

More exercise = increase calcitoninMore exercise = increase calcitonin

Increase in Calcitonin = increase in Increase in Calcitonin = increase in osteoblast formationosteoblast formation

More osteoblasts = increase in bone densityMore osteoblasts = increase in bone density

As you age, bone is broken down As you age, bone is broken down faster than it is renewed. faster than it is renewed.

Calcium is not as readily absorbed Calcium is not as readily absorbed in older womenin older women

Loss of Calcium Loss of Calcium in bones = Osteoperosisin bones = Osteoperosis

OsteoporosisOsteoporosis

Overview of Human SkeletonOverview of Human SkeletonAdult skeleton has 206 bonesAdult skeleton has 206 bones

Bone growth usually stops by age 20Bone growth usually stops by age 20

Appendicular Skeleton Appendicular Skeleton Bones of the Bones of the pectoral and pelvic girdlepectoral and pelvic girdle

Axial skeleton Axial skeleton bones of the skull, bones of the skull, spine, sternum, and ribsspine, sternum, and ribs

Infant skeletonInfant skeleton

adult skeletonadult skeleton

Appendicular SkeletonAppendicular SkeletonBones of the pectoral girdle are held together by ligamentsBones of the pectoral girdle are held together by ligaments

Bones of the Pectoral GirdleBones of the Pectoral GirdleClavicle Clavicle Collarbone Collarbone

Scapula Scapula Shoulder Blade Shoulder BladeClavicle connects to the sternum in the anterior and the scapula in the posteriorClavicle connects to the sternum in the anterior and the scapula in the posterior

Humerus Humerus single long bone of the upper arm single long bone of the upper armThe joint that connects the humerus to the scapula is very shallow, the The joint that connects the humerus to the scapula is very shallow, the attachment is unstable, often results in dislocated shoulders attachment is unstable, often results in dislocated shoulders

Ulna Ulna small bone of the lower arm; prominent bone in the elbow small bone of the lower arm; prominent bone in the elbow

Radius Radius other small bone of the lower arm; visceral to the ulna (palm down) other small bone of the lower arm; visceral to the ulna (palm down)

Carpals (8) Carpals (8) bones of the wrist bones of the wrist

Metacarpals (5) Metacarpals (5) bones of the medial hand bones of the medial hand

Phalanges (15) Phalanges (15) Bones of the digits Bones of the digits

Pectoral GirdlePectoral Girdle

Bones of the Pelvic GirdleBones of the Pelvic GirdleCoxal Bones (2) Coxal Bones (2) Hip Bones Hip BonesCoxal bones are wider in females than in malesCoxal bones are wider in females than in males

Sacrum ->Lower spineSacrum ->Lower spine

Coccyx Coccyx tailbone tailbone

Femur -> Thighbone (largest and strongest bone in the body (can withstand ~700 Femur -> Thighbone (largest and strongest bone in the body (can withstand ~700 pounds of downward force)pounds of downward force)

Tibia Tibia shin bone; larger of the 2 lower leg bones shin bone; larger of the 2 lower leg bones

Fibula Fibula smaller lower leg bone that reaches outer anklesmaller lower leg bone that reaches outer ankle

Tarsals (7) Tarsals (7) Bones of the ankle; distributes weight to heels and balls of your feet Bones of the ankle; distributes weight to heels and balls of your feet

Metatarsals (5) Metatarsals (5) bones of the inner foot bones of the inner foot

Phalanges (14) Phalanges (14) bones of the toes bones of the toes

Pelvic GirdlePelvic Girdle

Axial SkeletonAxial SkeletonBones of the Head and FaceBones of the Head and FaceCranium protects the brain & consists of 8 tightly fitted Cranium protects the brain & consists of 8 tightly fitted bones in adultsbones in adults

In infants, bones are not fit together tightly and are held In infants, bones are not fit together tightly and are held together by membranes called fontanels (gone by about together by membranes called fontanels (gone by about 1 year of age)1 year of age)

Infant skullInfant skull

Major Bones of the CraniumMajor Bones of the CraniumFrontal (1) Frontal (1) Forehead ForeheadParietal (2) Parietal (2) Sides of skull Sides of skullOccipital (1) Occipital (1) posterior of skull to its base, leads to foramen posterior of skull to its base, leads to foramen magnum (hole for spinal chord)magnum (hole for spinal chord)Temporal (2) Temporal (2) On sides of skull inferior to parietal bones On sides of skull inferior to parietal bonesSphenoid Bone (1) Sphenoid Bone (1) Anterior to temporal bone Anterior to temporal bone Ethmoid (1) Part of inner orbital wallEthmoid (1) Part of inner orbital wall

Facial BonesFacial BonesMandible Mandible Lower jaw (only movable portion of the skull) Lower jaw (only movable portion of the skull)Maxillary Bones Maxillary Bones Hold teeth and center nose Hold teeth and center nosePalatine Bone Palatine Bone . Make up the posterior portion of the hard . Make up the posterior portion of the hard palate & floor of the nasal cavitypalate & floor of the nasal cavityZygomatic Bones Zygomatic Bones Cheekbones and bridge of nose Cheekbones and bridge of noseLacrimal Bone Lacrimal Bone Lies between ethmoid and maxillary bone Lies between ethmoid and maxillary boneVomer Vomer Flat bone which forms the nasal septum Flat bone which forms the nasal septum

Cranium BonesCranium Bones

ParietalParietal

Facial BonesFacial Bones

Vertebral ColumnVertebral ColumnExtends from skull to PelvisExtends from skull to Pelvis

Intervertebral disks between the vertebrae act as padding. Intervertebral disks between the vertebrae act as padding. Prevent vertebrae from grinding against one anotherPrevent vertebrae from grinding against one another

These disks allow for flexibility (bending forward and backward)These disks allow for flexibility (bending forward and backward)

The 1st 7 disks (going from superior to inferior) are called the The 1st 7 disks (going from superior to inferior) are called the cervical vertebraecervical vertebrae

The next 12 disks are called the thoracic vertebraeThe next 12 disks are called the thoracic vertebrae

The lowest 5 vertebrae are called the lumbar vertebraeThe lowest 5 vertebrae are called the lumbar vertebraeSacrum connects the lumbar vertebrae to the tailbone (coccyx)Sacrum connects the lumbar vertebrae to the tailbone (coccyx)

Vertebral ColumnVertebral Column

Ligaments of the Knee (4)Ligaments of the Knee (4)

LCL

ACLMCL

PCLmeniscus

True Ribs, False Ribs, and Floating Ribs

JointsJointsJoints areas of contact between bonesEnds of bones are covered with cartilage to reduce friction

Synovial Joints 2 bones separated by a cavityLigaments connected the 2 bones togetherThe cavity is usually filled with fluid (synovial fluid) that lubricate the joint

Example—>The KneeThe knee is a unique synovial joint because it has lots of pieces of small cartilage that hold the knee in place

The added pieces of cartilage are called menisci

Fluid filled sacs called bursa have extra fluid to reduce friction between ligaments and tendons of the knee

Bursitis -> inflammation of the bursa sacs

JointsJoints

Bursa sacs

JointsJointsHinge Joints joints shaped like the hinges of a doorElbow is an example of a hinge joint (moves in one direction)

Ball and Socket Joints allow for rotation in all planesShoulder is an example of a ball and socket joint

Arthritis The synovial membrane (which holds synovial fluid) becomes inflamed and thickens (rheumatoid arthritis)

Osteoarthritis Cartilage at the end of the bone breaks down and wears away the bones

JointsJoints

Elbow

Hinge Joint

Moves in 1 Direction

Hip

Ball & Socket Joint

ArthritisArthritis

Osteoarthritis

Rheumatoid arthritis