CONCEPT MAP OF CHAPTER 2

LEARNING OUTCOMES To explain the necessity for support and locomotion in humans and animals,

To describe problems that could be faced by humans and animals in support and locomotion,

To explain how problems in support and locomotion are overcome in humans and animals,

To name the bones that make up the axial skeleton and appendicular skeleton of the human body

The Necessity for Support & Locomotion in Humans & AnimalsWHY DO HUMANS & ANIMALS NEED SUPPORT? To find the food To find partner for mating To protect/escape from their predator To shelter from bad environment

The Necessity for Support & Locomotion in Humans & AnimalsWithout support, animals & humans would not be able to maintain their body shape their body collapse under the weight of their own tissues.

Support are provided by some form of skeleton.Hydrostatic skeletonExoskeletonendoskeleton

HYDROSTATIC SKELETONA fluid-filled internal body cavity in which the fluid is held under pressure maintaining the body shape & providing support for internal organ

The cavity is surrounded by muscles arranged in layers.

The body shape of the animal changes as these muscles contract & relax.

The animals are soft & flexible, the hydrostatic fluid does protect body parts by acting as a shock absorber.Examples : earthworm, jellyfish, leech & caterpillar.

EXOSKELETONA rigid outer covering usually made up of protein, chitins &/@ calcium salt.

Insects the cuticle (covered with wax to prevent water loss from the body), cover the bodys surface.

The exoskeleton is jointed / hinged = certain points of the skeleton are flexible & can bend enabling the movement.

Exoskeleton restrict the growth of animals the exoskeleton must be shed from time to time in order for the animal to grow. (ecdysis)

Also found in the shells of molluscs & the bony plates of tortoises.

Examples : insects, crabs, lobsters, tortoise

ENDOSKELETONFound in the bodies of all vertebrates including fish, amphibians & birds.

Consist of hard skeleton of bones & cartilage found inside the body made up of calcium & phosphate.

Works with the muscular system to perform movement & locomotion. It support the body & protects the organs.

The Necessity for Support & Locomotion in Humans & AnimalsThe functions of skeleton :

Provide shape & supportEnables movement (locomotion)Protects internal organsStores calcium & phosphate ionsProduces blood cellsA firm base for the attachment of muscles

The Necessity for Support & Locomotion in Humans & AnimalsProblems that could be faced by humans and animals in support and locomotion,gravitational force, friction & resistance when moving aroundAspect need to be considered when describing the locomotion of an animal :-Stability when it moves, it is temporarily unstable, but its stability will be restored when it stops.Support must have enough support from its bodys skeletonPropulsion must be propelled in order to move

HOW TO OVERCOME THE PROBLEMS?RESISTANCE & FRICTION by streamlining their bodies.

GRAVITATIONAL FORCE most animals have their own supporting structures (fins fishes, wings birds & strong limbs tetrapods & humans) provide the propulsive force to overcome the problem

The skeletal system together with its muscles are designed specially to overcome the problems associated with support & locomotion of humans & animals.

To initiate locomotion, the force required is generated by contraction of muscles, whereas the movement is transmitted by the skeleton.

THE HUMAN SKELETAL SYSTEMThe adult human skeleton consist of 206 bones.

Divided into two main parts : the axial skeleton & the appendicular skeleton.

The axial skeleton : made up of the bones that form the vertical axis of the body.

It supports & protects the organs of the head, neck & trunk. (skull, vertebral column, rib cage)

The appendicular skeleton : made up of the bones that are attached to the axial skeleton.

Include bones of the limbs, the pectoral girdle & the pelvic girdle.

FUNCTION OF THE SKELETONPROTECTION the skull protects the brain, the vertebral column protects the spinal cord & the rib cage protects internal organs such as the heart.

SUPPORT act as a framework to support the soft body parts, to maintain the upright position & to keep the body stable.

FUNCTION OF THE SKELETONMOVEMENT bones interact with the skeletal muscle.

BLOOD CELL FORMATION most of the blood cells are formed in the bone marrow of the long bones.

MINERAL STORAGE bones act as a reservoir for calcium & phosphorus.

SKELETAL SYSTEM

THE SKULLMade up of 8 cranial bones & 14 facial bones including the upper jaw & the lower jaw.

The facial bones also provide support & protect the entrances to the respiratory system.

SKULL

VERTEBRAL COLUMNKnown as the spine/ backbone.

Extends from the base of the skull to the pelvic girdle.

Made up of 33 vertebrae separated from each other by discs of cartilage (intervertebral discs) which absorb shocks & serve as flex point.

This S-shaped column supports & balances the body in a vertical plane & protects the spinal cord, supports the skull & provides a base for the attachment of muscles to the back.

VERTEBRAL COLUMNThe vertebrae differ in structure & function in different regions of the vertebral column.

A vertebra typically consists of a main body (the centrum), a neural arch & transverse processes.

VERTEBRAL COLUMN

VERTEBRAL COLUMN

TYPES OF VERTEBRAE

CERVICAL VERTEBRA

THORACIC VERTEBRA

TYPE OF VERTEBRAEPOSITIONNUMBER OF VERTEBRAEMAIN CHARACTERThoracic VertebraThorax12 Neural canal/ vertebral foramen is smaller than cervical vertebras

Long neural spine/ spinous processes (for attachment of back muscle)

Thick & big centrum

Short transverse processes

THORACIC VERTEBRA (12)

LUMBAR VERTEBRA

TYPE OF VERTEBRAEPOSITIONNUMBER OF VERTEBRAEMAIN CHARACTERLumbar VertebraWaist5 small neural canal/ vertebral foramen

short neural spine

thick & big centrum

long transverse processes for muscle attachment

LUMBAR VERTEBRA

SACRUM & COCCYX

TYPE OF VERTEBRAEPOSITIONNUMBER OF VERTEBRAEMAIN CHARACTERSacrumPelvic region5 fused Vertebrae fused to each other

Has four pairs of openings

Triangular shapeCoccyxCaudal region4 fused Bones fused to each other forming a triangular shape which tapers at one end

SACRUM & COCCYX

The rib cage consists of 12 pairs of ribs with the thoracic vertebrae at the back portion of the body & join to the sternum in the front portion.

Movement of the rib cage are brought about by intercostal muscles between the ribs.THE STERNUM & RIBS

The sternum & ribs enclose & protect the internal organs (the lungs & heart) & play an important role in breathing.THE STERNUM & RIBS

Consist of scapula & clavicle.

Links the upper limbs bones to the axial skeleton.

The scapula : bound by muscles to the back of the thorax. It is a flat, triangular bone which provides a surface for the attachment of muscles.PECTORAL GIRDLE

The clavicle : a rod-shaped bone placed horizontally above the scapula.

It links the scapula to the sternum. It limits the movements of the scapula.

Consists of 6 fused bones support the weight of the body from the vertebral column.

Also protect the internal organs urinary bladder & reproductive organs.

Made up of two halves, each consists of 3 bones (ilium, pubis & ischium)PELVIC GIRDLE

The pelvic girdle is attached to the sacrum of the vertebral column.

The asetabulum / socket for femur articulates with each side of the pelvic girdle at the hip joint.PELVIC GIRDLE

FORELIMB BONESConsists of humerus, radius & ulna.

The Humerus : The long bones of the upper armRounded head end fits into an open socket of the scapula forming a ball-and-socket joint (allow movement in all planes)

The posterior end of the humerus forms a hinge joint with the ulna with the ulna-radius bones, allowing movement in one plane only.

The radius & ulna :The bones on the forearm in which the ulna is longer than the radius.It has a notch at its upper end which articulates the humerus at the elbow.

The carpals :The bones that form the wrist.Consists of 8 small bones

The metacarpals :The rod-shaped ones that form the palm.

The phalanges :The bones that form the fingers.

HINDLIMB BONESConsists of femur, tibia & fibula.

The femur :The longest, strongest & heaviest bone in the body.Support the tight.Play an important role in maintaining the bodys upright position & in locomotion as it is attached to massive muscles.The head of femur fits into the pelvic girdle to form a joint.Other end, articulates with the tibia & fibula at the knee.

The tibia & fibula :The bones of the lower leg.Support the shank.Tibia larger than fibula & is the weight-bearing bone of the leg.Fibula is a long & thin bone not bear any load more important for attachment of muscles than for support.Articulate with the tarsals of the ankle.

The tarsals :The 7 bones that form the ankle.

The metatarsals :The 5 rod-shaped bones that form the foot.

The phalanges :The bones that form the toes.

The patella/kneecap :A small rounded, movable bone.Protect the knee joint.