Secondary TwoTopic: Bones and JointsSub Topic: Functions of

Skeleton

Content Purpose• Students will understand the functions of the skeleton.

• Students will be able to list the four types of bones and state an example for each type.

Language Purpose• Long bones

• Short bones• Flat bones• Irregular bones

Social Purpose• One conversation• No sleeping• Putting of palm on whiteboard• Class too noisy and need to

quieten down

Today’s LessonGet into house levelEach house will be required to

research on a type of bone and present the findings during second period◦Cypress – Long bone and its

functions◦Jacaranda – Short bone and its

functions◦Aspen – Flat bone and its functions◦Carova – Irregular bone and its

functions

Before we start…

Which type of bone is this?

This is the skeleton of our hand

Ans.: Long bone

Group DiscussionAt the end of the discussion,

each group will be an expert in the type of bone assigned. Everyone in the group must be able to:◦Describe the type of bone assigned.◦List an example of the type of bone

assigned.◦Name a function of the type of bone

assigned.

PRESENTATION TIME!

LONG BONECypress House

Long BoneBones that have diaphysis,

epiphysis and a hollow centre.Cylindrical in shape, which gives

rise to the name “long” bone.Need not be physically long.Eg. Phalanges (fingers), upper

and lower arms / legs, etc.

Long BoneLong bones generally used for

actions that require long range of movements, eg. tossing of ball◦Act as a lever to efficiently bring

about rapid movement.Long bones also determine

height, shoe size, etc

Which are the long bones?

SHORT BONEJacaranda House

Short BoneSmall and

squat.Spongy

bone covered with a thin layer of compact bone.

Light and very strong.

Short BoneProvides

movement which need a range of directions.

Located mainly at wrist, ankle and knee.

HOW MANY BONES ARE THERE IN THE WRIST?

Ans.: 8

FLAT BONEAspen House

Flat BoneCharacterised by the flatness and

large surface area.Spongy bone between 2 layers of

compact bone.

Flat BoneProtect delicate

organs.Give big surface

area for muscle attachments.

Examples: Scapula (collar bone), cranium (skull), pelvis (hip bone), ribs.

IRREGULAR BONECarova House

Irregular BoneAny shape of bone that does not

fit into the earlier 3 categories.Spongy bones inside, compact

bone outside.

Irregular BoneShaped to suit the specific jobs.Example:

◦Back bone (vertebrae) to protect spinal cord, lower jaw (mandible) to hold the teeth for chewing.

General Functions of BoneShapeSupportProtectionMovementBlood production

Functions of Bone – ShapeThe skeleton gives rise to the

shape of human by providing a framework.

Without the skeleton, we will look like a lump of flesh.

Functions of Bone – SupportKeeps internal organs in place.Examples:

◦Skull keeps brain in place.◦Chest cavity holds lungs and heart in

place.Provides point of attachment for

muscles.

Functions of Bone – Support Girl born almost without bone –

Janelly Martinez-Amador

Functions of Bone – ProtectionProtect delicate organs.

◦Ribs protecting lungs and heart.◦Skull protecting brain.

Functions of Bone – MovementMuscles are attached to bones.Muscles contract and pull the

bones, which give rise to the movement.

Functions of Bone – Blood ProductionBlood is produced in the marrow

cavity (red marrow).Approximately 2.4 – 2.6 million

red blood cells are produced every second.

Lets Recap!Name the 4 types of bones that

we had covered today.What are the 5 functions of

human skeleton?