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The Human Skeleton The Human Skeleton

The Human Skeleton The Skeletal System Slide 5.1 Parts of the skeletal system Bones (skeleton) Joints Cartilages Ligaments (bone to bone)(tendon=bone

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Page 2: The Human Skeleton The Skeletal System Slide 5.1  Parts of the skeletal system  Bones (skeleton)  Joints  Cartilages  Ligaments (bone to bone)(tendon=bone

The Skeletal SystemThe Skeletal System

Slide 5.1

Parts of the skeletal system

Bones (skeleton)

Joints

Cartilages

Ligaments (bone to bone)(tendon=bone to muscle)

Divided into two divisions

Axial skeleton

Appendicular skeleton – limbs and girdle

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Functions of the Skeletal Functions of the Skeletal SystemSystem

Provides shape and formProvides shape and form Supporting, protecting, and allowing Supporting, protecting, and allowing

bodily movementbodily movement Produces blood for blood cellsProduces blood for blood cells Storing mineralsStoring minerals

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The Skeleton Is Divided Into The Skeleton Is Divided Into Two Distinct Parts:Two Distinct Parts:

THE AXIAL SKELETON CONSISTS THE AXIAL SKELETON CONSISTS OF BONES THAT FORM THE AXIS OF BONES THAT FORM THE AXIS OF THE BODY AND SUPPORT AND OF THE BODY AND SUPPORT AND PROTECT THE ORGANS OF THE PROTECT THE ORGANS OF THE HEAD, NECK, AND TRUNK.HEAD, NECK, AND TRUNK.

THE APPENDICULAR SKELETON IS COMPOSED OF BONES THAT ANCHOR THE APPENDAGES TO THE AXIAL SKELETON.

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B1. Human Endoskeleton B1. Human Endoskeleton made ofmade of

a.a. Axial:Axial: skull, skull, backbone, ribs, backbone, ribs, sternumsternum

b.b. Appendicular:Appendicular: arms, legs, arms, legs, shoulders, shoulders, hips,wrists, hips,wrists, anklesankles

Boo !

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The Axial SkeletonThe Axial Skeleton

Slide 5.20b

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Figure 5.6

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The SkullThe Skull

Slide 5.21a

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Two sets of bones

Cranium

Facial bones

Bones are joined by sutures

Only the mandible is attached by a freely movable joint

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Bones of the SkullBones of the Skull

Slide 5.22Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Figure 5.11

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The Fetal SkullThe Fetal Skull

Slide 5.27a

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The fetal skull is large compared to the infants total body length

Figure 5.13

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The Fetal SkullThe Fetal Skull

Slide 5.27b

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Fontanelles – fibrous membranes connecting the cranial bones

Allow the brain to grow

Convert to bone within 24 months after birth

Figure 5.13

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The Hyoid BoneThe Hyoid Bone

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The only bone that does not articulate with another bone

Serves as a moveable base for the tongue

Figure 5.12

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The Vertebral ColumnThe Vertebral Column

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Vertebrae separated by intervertebral discs

The spine has a normal curvature

Each vertebrae is given a name according to its location Figure 5.14

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The Bony ThoraxThe Bony Thorax

Slide 5.31a

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Forms a cage to protect major organs

Figure 5.19a

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The Bony ThoraxThe Bony Thorax

Slide 5.31b

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Made-up of three parts

Sternum

Ribs

Thoracic vertebrae

Figure 5.19a

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The Appendicular SkeletonThe Appendicular Skeleton

Slide 5.32a

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Limbs (appendages)

Pectoral girdle

Pelvic girdle

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The Appendicular SkeletonThe Appendicular Skeleton

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The Pectoral (Shoulder) GirdleThe Pectoral (Shoulder) Girdle

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Composed of two bones

Clavicle – collarbone

Scapula – shoulder blade

These bones allow the upper limb to have exceptionally free movement

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Bones of the Shoulder GirdleBones of the Shoulder Girdle

Slide 5.34a

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Bones of the Upper LimbBones of the Upper Limb

Slide 5.35a

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The arm is formed by a single bone

Humerus

Figure 5.21a, b

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Bones of the Upper LimbBones of the Upper Limb

Slide 5.35b

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• The forearm has two bones

• Ulna

• Radius

Figure 5.21c

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Bones of the Upper LimbBones of the Upper Limb

Slide 5.36Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

The hand

Carpals – wrist

Metacarpals – palm

Phalanges – fingers

Figure 5.22

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The PelvisThe Pelvis

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Gender Differences of the PelvisGender Differences of the Pelvis

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Figure 5.23c

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Bones of the Lower LimbsBones of the Lower Limbs

Slide 5.40a

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The thigh has one bone

Femur – thigh bone

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Bones of the Lower LimbsBones of the Lower Limbs

Slide 5.40b

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

The leg has two bones

Tibia

Fibula

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Bones of the Lower LimbsBones of the Lower Limbs

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

The foot

Tarsus – ankle

Metatarsals – sole

Phalanges – toes

Figure 5.25

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Bones of the Pelvic GirdleBones of the Pelvic Girdle

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HIP BONES COMPOSED OF THREE PAIR OF FUSED BONES

ILIUM ISCHIUM PUBIC BONE

THE TOTAL WEIGHT OF THE UPPER BODY RESTS ON THE PELVIS PROTECTS SEVERAL ORGANS

REPRODUCTIVE ORGANS URINARY BLADDER PART OF THE LARGE INTESTINE

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Endoskeletons also Endoskeletons also have…….have…….

1c.1c. Ligaments Ligaments that hold bone to that hold bone to bonebone

1d. 1d. TendonsTendons that hold muscle to that hold muscle to bone, “muscle tenders”bone, “muscle tenders”

1e.1e. Joints Joints where 2 bones come where 2 bones come togethertogether

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Types of BonesTypes of BonesTHE BONES OF THE BODY FALL INTO FOUR

GENERAL CATEGORIES: LONG BONES, SHORT

BONES, FLAT BONES, AND IRREGULAR BONES.

LONG BONES ARE LONGER THAN THEY ARE

WIDE AND WORK AS LEVERS. THE BONES OF

THE UPPER AND LOWER EXTREMITIES ARE OF

THIS TYPE. SHORT BONES ARE SHORT, CUBE-

SHAPED, AND FOUND IN THE WRISTS AND

ANKLES.

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FLAT BONES HAVE BROAD SURFACES FOR FLAT BONES HAVE BROAD SURFACES FOR

PROTECTION OF ORGANS AND PROTECTION OF ORGANS AND

ATTACHMENT OF MUSCLES IRREGULARATTACHMENT OF MUSCLES IRREGULAR

BONES ARE ALL OTHERS THAT DO NOT BONES ARE ALL OTHERS THAT DO NOT FALLFALL

INTO THE PREVIOUS CATEGORIES. THEYINTO THE PREVIOUS CATEGORIES. THEY

HAVE VARIED SHAPES, SIZES, AND HAVE VARIED SHAPES, SIZES, AND

SURFACES FEATURES AND INCLUDE THE SURFACES FEATURES AND INCLUDE THE

BONES OF THE VERTEBRAE AND A FEW IN BONES OF THE VERTEBRAE AND A FEW IN

THE SKULL.THE SKULL.

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Classification of Bones on the Classification of Bones on the Basis of ShapeBasis of Shape

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Bone CompositionBone Composition

Bones are composed of tissue that may take one of two forms. Compact, or dense bone, and spongy, or cancellous, bone. Most bones contain both types. Compact bone is dense, hard, and forms the protective exterior portion of all bones. Spongy bone is inside the compact bone and is very porous (full of tiny holes). Spongy bone occurs in most bones. The bone tissue is composed of several types of bone cells embedded in a web of inorganic salts (mostly calcium and phosphorus) to give the bone strength, and collagenous fibers and ground substance to give the bone flexibility.

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Types of jointsTypes of joints

(joints are also called (joints are also called articulations)articulations)

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FUNCTIONAL CLASSIFICATION FUNCTIONAL CLASSIFICATION OF JOINTSOF JOINTS

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SYNARTHROSES – IMMOVABLE JOINTS

AMPHIARTHROSES – SLIGHTLY MOVEABLE JOINTS

DIARTHROSES – FREELY MOVEABLE JOINTS

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FIBROUS JOINTSFIBROUS JOINTS

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BONES UNITED BY FIBROUS TISSUE – SYNARTHROSIS OR LARGELY IMMOVABLE.

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SYNOVIAL JOINTSSYNOVIAL JOINTS FREELY MOVEABLE JOINTSFREELY MOVEABLE JOINTS ENCAPSULATED BY CONNECTIVE TISSUEENCAPSULATED BY CONNECTIVE TISSUE THE CONNCTIVE TISSUE SECRETES THE CONNCTIVE TISSUE SECRETES

SYNOVIAL FLUIDSYNOVIAL FLUID

THE EPIPHYSIS OF THE BONES IS THE EPIPHYSIS OF THE BONES IS COVERED WITH CARTILAGECOVERED WITH CARTILAGE

HAVE TENDONS AND LIGAMENTS HAVE TENDONS AND LIGAMENTS AROUND THEMAROUND THEM

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CARTILAGINOUS JOINTS – CARTILAGINOUS JOINTS – MOSTLY AMPHIARTHROSISMOSTLY AMPHIARTHROSIS

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Bones connected by cartilage

Examples

Pubic symphysis

Intervertebral joints

Figure 5.27b, c

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Types of synovial jointsTypes of synovial joints Gliding joints, the articulating Gliding joints, the articulating

surfaces are typically flatsurfaces are typically flat

Hinge joints, found in the fingers and Hinge joints, found in the fingers and elbow; the spoon-like surface fits into elbow; the spoon-like surface fits into a concave surfacea concave surface

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Ball and socket, shoulder joint; where Ball and socket, shoulder joint; where a ball fits into a cuplike depressiona ball fits into a cuplike depression

Pivot joints, found between the Pivot joints, found between the proximal ends of the radius and ulna; proximal ends of the radius and ulna; surface fits into a ring formed by surface fits into a ring formed by bone and ligamentbone and ligament

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THE SYNOVIAL JOINTTHE SYNOVIAL JOINT

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Figure 5.28

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CARTILAGINOUS JOINTS CARTILAGINOUS JOINTS

CARTILAGE FILL THE SPACE CARTILAGE FILL THE SPACE BETWEEN THE JOINTS, ALLOWING BETWEEN THE JOINTS, ALLOWING ONLY A LITTLE MOTIONONLY A LITTLE MOTION

BETWEEN VERTEBRAEBETWEEN VERTEBRAE

BETWEEN STERNUM AND RIBSBETWEEN STERNUM AND RIBS

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FIBROUS JOINTSFIBROUS JOINTS

FIBROUS CONNECTIVE TISSUE FIBROUS CONNECTIVE TISSUE JOINS THE BONES (FONTANELLES)JOINS THE BONES (FONTANELLES)

NO REAL SPACE BETWEEN BONESNO REAL SPACE BETWEEN BONES

ALLOWS BONES OF SKULL TO ALLOWS BONES OF SKULL TO CROSS DURING CHILDBIRTHCROSS DURING CHILDBIRTH

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Types of JointsTypes of Joints

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CHANGES IN THE HUMAN CHANGES IN THE HUMAN SKELETONSKELETON

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In embryos, the skeleton is primarily hyaline cartilage

During development, much of this cartilage is replaced by bone

Cartilage remains in isolated areas

Bridge of the nose

Parts of ribs

Joints

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BONE GROWTHBONE GROWTH

Slide 5.13a

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Epiphyseal plates allow for growth of long bone during childhood

New cartilage is continuously formed

Older cartilage becomes ossified

Cartilage is broken down

Bone replaces cartilage

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Joint Damage: Joint Damage: ArthritisArthritis

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Bone Deformation: Lack of Bone Deformation: Lack of Vitamin DVitamin D

“Bow-legged”

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BONE FRACTURESBONE FRACTURES

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A break in a bone

Types of bone fractures

Closed (simple) fracture – break that does not penetrate the skin

Open (compound) fracture – broken bone penetrates through the skin

Bone fractures are treated by reduction and immobilization

Realignment of the bone

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COMMON TYPES OF FRACTURESCOMMON TYPES OF FRACTURES

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Page 55: The Human Skeleton The Skeletal System Slide 5.1  Parts of the skeletal system  Bones (skeleton)  Joints  Cartilages  Ligaments (bone to bone)(tendon=bone

Thighbones are usually stronger, pound for Thighbones are usually stronger, pound for pound, than reinforced concrete.pound, than reinforced concrete.

Men's bones tend to be larger and heavier Men's bones tend to be larger and heavier than women's bones.than women's bones.

The hip bone is actually six bones joined to The hip bone is actually six bones joined to the sacrum to form the pelvisthe sacrum to form the pelvis

There are 230 joints in the bodyThere are 230 joints in the body The femur is the longest bone in the bodyThe femur is the longest bone in the body You shrink 1/2" during the day, due to You shrink 1/2" during the day, due to

compression of the spinal columncompression of the spinal column Bones are 1/5 of the total body weightBones are 1/5 of the total body weight There are 26 bones in the footThere are 26 bones in the foot The last bone to mature is the collar boneThe last bone to mature is the collar bone One in 20 people has an extra ribOne in 20 people has an extra rib The smallest bone in your body, located The smallest bone in your body, located

in your ear, is smaller than a grain of ricein your ear, is smaller than a grain of rice

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Is The Funny Bone Really Funny?Is The Funny Bone Really Funny?Actually, the funny bone has nothing to do with Actually, the funny bone has nothing to do with laughter. In fact, it isn't even a bone at all. It is laughter. In fact, it isn't even a bone at all. It is really a nerve called the really a nerve called the ulnar nerveulnar nerve. But, it runs . But, it runs right next to the "humerus." Get it? "Humerus." right next to the "humerus." Get it? "Humerus." That's where "funny bone" comes from.That's where "funny bone" comes from.

When you bend your elbow, you have this ulnar When you bend your elbow, you have this ulnar nerver that is much easier to get to than most nerver that is much easier to get to than most nerves are. So, when you hit your elbow, the nerve nerves are. So, when you hit your elbow, the nerve also gets whacked and begins to send messages also gets whacked and begins to send messages that travel all the way up your arm, to your spinal that travel all the way up your arm, to your spinal cord and along your spinal cord to your brain. cord and along your spinal cord to your brain.

The result: a tingling sensation that shoots from The result: a tingling sensation that shoots from your elbow, where the impact occurred, to the tip of your elbow, where the impact occurred, to the tip of your little finger (which is where the nerve ends). your little finger (which is where the nerve ends).

That's why it hurts. Not so funny, is it?That's why it hurts. Not so funny, is it?

(Sources include: (Sources include: Science WebScience Web, , GuardianGuardian

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