The Skeletal system, A presentation for Grade Elevens

SUPPORT SYSTEMS IN

ANIMALS

A PRESENTATION FOR GRADE 11S

EXOSKELETON

• SOME INVERTEBRATES HAVE HARD EXTERNAL STRUCTURES FOR :

1.MAINTAINING THEIR SHAPE

2.SUPPORTING THEIR BODIES

3.PROTECTING THEIR INTERNAL BODY ORGANS

4.AIDING MOVEMENT

• THE HARD EXTERNAL STRUCTURES ARE CALLED EXOSKELETONS

• THE EXOSKELETONS CONSISTS OF A HARD SUBSTANCE CALLED CHITIN

HYDROSTATIC SKELETON

• INVERTEBRATES WITH SOFT BODIES HAVE BODY FLUIDS TO PROVIDE THEM WITH SHAPE AND SUPPORT

• THE BODY FLUIDS EXERT A PRESSURE ON THEIR BODY WALLS TO FORM A HYDROSTATIC SKELETON

• THE HYDROSTATIC SKELETON HAS THE FOLLOWING FUNCTIONS :

1.PROVIDES SUPPORT

2.MAINTAINS BODY SHAPE

3.AIDS MOVEMENT

EXOSKELETON• AQUATIC INVWERTEBRATES SUCH AS PRAWNS, CRABS,

COCKLES AND SNAILS ARE SUPPORTED BY HARD EXOSKELETON

• THE EXOSKELETONS ARE VERY HARD BECAUSE THEY CONTAIN CALCIUM

HYDROSTATIC SKELETON• AQUATIC INVERTEBRATES

SUCH AS THE STARFISH AND THE JELLYFISH ARE SUPPORTED BY A HYDROSTATIC SKELETON

• THE FLUID PRESSURE IN THEIR BODIES GIVES THEM SUPPORT AND SHAPE

The Skeletal SystemThe Skeletal System The skeletal system consists of:

Bones (skeleton)

Joints

Cartilages

Ligaments (connect bone to bone)

tendon=( connect bone to muscle)

Divided into two parts

Axial skeleton

Appendicular skeleton – limbs and girdle

Functions of BonesFunctions of Bones

Support then weight of the body

Give the body its structure and shape

Protection of soft organs

Movement due to attached skeletal muscles

Storage of minerals and fats

Blood cell production

Bones of the Human BodyBones of the Human Body

The skeleton has 206 bones

Two basic types of bone tissue

Compact bone

Homogeneous

Spongy bone

Small needle-like pieces of bone

Many open spaces

Bones are classified by their shape.

There are:1.long 2.short 3.flat 4.irregular bones.

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

Gross Anatomy of a Long BoneGross Anatomy of a Long Bone

Diaphysis

Shaft

Composed of compact bone

Epiphysis

Ends of the bone

Composed mostly of spongy bone

A Microscopic View of the BoneA Microscopic View of the Bone

Structures of a Long BoneStructures of a Long Bone Periosteum

Outside covering of the diaphysis

Fibrous connective tissue membrane

Sharpey’s fibers Secure periosteum to

underlying bone

Arteries Supply bone cells

with nutrients

Types of Bone CellsTypes of Bone Cells Osteocytes

Mature bone cells

Osteoblasts Bone-forming cells

Osteoclasts Bone-destroying cells

Break down bone matrix for remodeling and release of calcium

Bone remodeling is a process by both osteoblasts and osteoclasts

Bone FracturesBone Fractures

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

Common Types of FracturesCommon Types of Fractures

Axial skeleton supports and protects organs of head, neck and trunk Axial skeleton:• skull (cranium and facial bones)• hyoid bone (anchors tongue and muscles• associated with swallowing)• vertebral column (vertebrae and disks)• bony thorax (ribs and sternum) Appendicular skeleton includes bones of limbs and

bones that anchor them to the axial skeletonAppendicular skeleton:• pectoral girdle (clavicles and scapulae)• upper limbs (arms)• pelvic girdle (sacrum, coccyx)• lower limbs (legs)Articulation- where joints meet, connect, and are formed.

• 22 bones in skull• 6 in middle ears• 1 hyoid bone• 26 in vertebral

column• 25 in thoracic cage

• 4 in pectoral girdle• 60 in upper limbs• 60 in lower limbs• 2 in pelvic girdle

• 206 bones in all

The Axial SkeletonThe Axial Skeleton

Forms the longitudinal part of the body

Divided into three parts

Skull

Vertebral column

Bony thorax

The Axial SkeletonThe Axial Skeleton

The skull

8 sutured bones in craniumFacial bones: 13 sutured bones, 1 mandible

Craniumencases brainattachments for musclessinuses

Bones of the Skull

Allows forgrowth

The Vertebral ColumnThe Vertebral Column

Vertebrae separated by intervertebral discs

The spine has a normal curvature

Each vertebrae is given a name according to its location

Vertebral column

7 cervial vertebrae12 thoracic5 lumbar1 sacrum (5 fused 1 coccyx (4 fused)

Vertebrae vary in size and morphology

Structure of a Typical VertebraeStructure of a Typical Vertebrae

Thoracic cage• ribs• thoracic vertebrae• sternum• costal cartilages

True ribs are directly attached to the sternum(first seven pairs)Three false ribs are joined to the 7th ribTwo pairs of floating ribs

JOINTS• FIBROUS- CONNECT BONES WITHOUT ALLOWING

ANY MOVEMENT. BONES OF THE SKULL AND PELVIS.

• CARTILAGINOUS- THE BONES ARE ATTACHED BY CARTILAGE. ALLOW FOR ONLY A LITTLE MOVEMENT, SPINE OR RIBS.

• SYNOVIAL- MORE MOVEMENT. CAVITIES BETWEEN BONES IN SYNOVIAL JOINTS

ARE FILLED WITH SYNOVIAL FLUID. FLUID LUBRICATES AND PROTECTS THE BONES.

BURSA SACKS CONTAIN THE SYNOVIAL FLUID WITHIN FIXED LIMITS

• A JOINT, OR ARTICULATION, IS THE PLACE WHERE TWO BONES COME TOGETHER.

• THERE ARE THREE TYPES OF JOINTS CLASSIFIED BY THE AMOUNT OF MOVEMENT

• THEY ARE:

IMMOVABLE SLIGHTLY MOVABLE FREELY MOVABLE

TYPES OF JOINTS

HINGE- A HINGE JOINT ALLOWS EXTENSION AND

RETRACTION OF AN APPENDAGE. (ELBOW,

KNEE)

BALL AND SOCKET- A BALL AND SOCKET JOINT ALLOWS

FOR RADIAL MOVEMENT IN ALMOST ANY DIRECTION.

THEY ARE FOUND IN THE HIPS AND SHOULDERS. (HIP,

SHOULDER)

GLIDING- IN A GLIDING OR PLANE JOINT BONES

SLIDE PAST EACH OTHER. MID-CARPAL AND MID-

TARSAL JOINTS ARE GLIDING JOINTS. (HANDS,

FEET)

SADDLE- THIS TYPE OF JOINT OCCURS WHEN THE TOUCHING SURFACES OF TWO BONES HAVE BOTH CONCAVE AND CONVEX REGIONS WITH THE SHAPES OF THE TWO BONES COMPLEMENTING ONE OTHER AND ALLOWING A WIDE RANGE OF MOVEMENT. (THUMB)

Structures Associated with the Structures Associated with the Synovial JointSynovial Joint Bursae – flattened fibrous sacs

Lined with synovial membranes

Filled with synovial fluid

Not actually part of the joint

Tendon sheath

Elongated bursa that wraps around a tendon

The Synovial JointThe Synovial Joint

Types of Synovial Joints Based on Types of Synovial Joints Based on ShapeShape

Types of Synovial Joints Based on Types of Synovial Joints Based on ShapeShape

DISEASES AND CONDITIONS

OF THE SKELETAL SYSTEM

ARTHRITIS

OSTEOPOROSIS• MEANS "POROUS BONES."

• BONES HAVE LOST MINERALS

(ESPECIALLY CALCIUM) MAKING THEM

WEAK, BRITTLE, AND SUSCEPTIBLE TO

FRACTURES

• MOST COMMON PLACES WHERE

FRACTURES OCCUR ARE THE BACK,

HIPS, AND WRISTS.

TENDONITIS• INFLAMMATION OF THE TENDON.

• MOVEMENT BECOMES PAINFUL.

• MOST COMMON CAUSE OF TENDONITIS IS

OVERUSE.

RICKETS

• SOFTENING AND WEAKENING OF BONES

IN CHILDREN

• USUALLY BECAUSE OF AN EXTREME AND

PROLONGED VITAMIN D DEFICIENCY.

GOUT• RESULTS FROM AN OVERLOAD OF URIC

ACID IN THE BODY.

• LEADS TO THE FORMATION OF URATE CRYSTALS THAT DEPOSIT IN THE JOINTS.

• CRYSTALS IN THE JOINTS CAUSES RECURRING ATTACKS OF JOINT INFLAMMATION (ARTHRITIS).

• CHRONIC GOUT MAY CAUSE JOINT DESTRUCTION, DECREASED KIDNEY FUNCTION, AND KIDNEY STONES.

REFERENCES• HTTP://BESTCLIPARTBLOG.COM/22-SKELETON-CLIP-

ART.HTML/SKELETON-CLIP

• RANUM, M. J. (2008). BONES. AVAILABLE FROM: HTTP://MJRANUM-STOCK.DEVIANTART.COM/ART/BONES. ACCESSED: 7 MARCH 2014

• ERASMUS, B. (2012). ANIMAL SUPPORT SYSTEM. AVAILABLE FROM: HTTP://WWW.SLIDESHARE.NET/B_ERASMUS/ANIMAL-SUPPORT-SYSTEM. ACCESSED: 7 MARCH 2014

• SEVC, T. K. (2014). SKELETAL SYSTEM. AVAILABLE FROM: HTTP://WWW.SLIDESHARE.NET/MRSSEVCTK/SKELETAL-SYSTEM. ACCESSED: 7 MARCH 2014

• KAHN, M.T. [N.D.]. THE SKELETAL SYSTEM. AVAILABLE FROM: HTTP://WWW.SLIDESHARE.NET/IQBAL1313/THE-SKELETAL-SYSTEM. ACCESSED: 7 MARCH 2014