Exploring Human Skeleton Aseel Samaro Human skeleton There

Exploring Human Skeleton Aseel Samaro

Human skeleton There are 206 bones in the human skeleton. which one is the smallest? which one is the largest? Each one contains calcium to make it strong.

Bones make up the human skeleton. Without your skeleton you would flop! The main bones of the human skeleton

Investigating the structure of the bone § Bones must be strong to support you. § Most of the bones (approximately 70 per cent) is made up of hard minerals, such as calcium. § The outside of a bone is smooth and hard to provide support. § Inside this hard outer layer lies spongy, porous material This spongy layer allows your bones to bend slightly. § It also makes your bones lighter than if they were completely solid. § At the centre of a bone is a softer substance called marrow.

Comparing bones § Some bones are long and narrow, such as those in your arms. § Some bones are shorter, such as those in your feet. Femur § Other bones are flat and wide, such as the scapula (shoulder blade). § Each bone is adapted to suit its function. For example, the foot contains many small bones to allow flexibility. Scapula

Q. 7 Page 11 For each of the examples below, describe how the bone shape or structure is well adapted for its function in the body: üFemur (thigh bone) long and wide: gives strength to support the body weight üBones of the hand Many small bones with joints: allows the hand to bend in different directions üRibs curved: to protect lungs inside the chest cavity

What feature of bird’s bone help them to fly ? § The structure of bone in bird has perfectly adapted to the function of flying § Many bones in birds are hollow. They are full of air § This makes them lighter and, therefore, less energy is needed for them to fly

Analysing the skeleton The human skeleton has four main roles: üSupports the body üProtects the organs üAllows movement üProduces blood cells. § Without a skeleton you would not be able to sit, stand or hold yourself up.

§ The ribs are curved bones, forming a cavity inside the ribcage. The lungs are positioned inside the ribcage. § The many joints in your skeleton allow you to move. For example, the joint at the knee allows your leg to bend. Without joints, your skeleton would be rigid.

Did you know ? § Your ears and the end of your nose do not contain bone. Instead, these body parts are given their shape by cartilage. § Cartilage is softer than bone and does not contain blood vessels or nerve cells. Bone

Explain which organ each part of the skeleton protects: üRibs üCranium

Describe three parts of the skeleton where joints are important.

The importance of bone marrow § Bone marrow is in the centre of large bones. § It is here where blood cells are made. There are three types of blood cells : üRed blood cells carrying oxygen üWhite blood cells üPlatelets. § Patients with some medical conditions cannot make their own healthy blood cells. § If a bone marrow transplant is carried out the patient may then make healthy blood cells again.

What is meant by transplant? Transplant: transferring living tissue from one person to another

Using Bone Measurements § Your skeleton has many symmetrical features. § This helps you to balance and co-ordinate movements. § Skeletons are usually made in similar proportions. For example, if you stretch your arms as wide as you can and measure their arm span, this will probably be similar to your height. § At an archaeological dig or a crime scene, only a few bones may be found. § Yet scientists can predict the height of a person using only the length of: ü The femur ü Humerus ü the smaller bones in the arms and legs.

The calculation used to estimate height from the length of the femur is: § height (m) = (length of femur (m) × 2. 6) + 65

§ A femur, 0. 35 m in length, is found during a police investigation. Estimate the height of the victim. (Remember units). Estimate the arm span of the same victim.

Using Bone Measurements Calculation is not always accurate in people between 12 and 18 years of age. WHY ? ?

Thank you