Grade Five Science
How is everything going? Are you enjoying your holiday period? I hope you are, and I hope that you are reading and playing and finding out about all kinds of things.
We have been looking at various types of weather and at weather instruments for the past few weeks. This week we will begin investigating another topic. We will investigate our bodies and how they work.
All living things, including humans, have bodies that are built to perform vital functions that we need for our day-to-day living. Our human body is a marvellous, wonderful and amazing structure. It is complicated, too! Can you tell what it is made up of? Yes, it is made up of cells, which make up tissues. These tissues, in turn, make up organs, that help to form the body systems. These all work together to keep us alive. These systems, (about ten major ones) are arranged to be able to perform complex functions for the body. Can you name a few of these functions?
Take a look at the organs in the picture below. Do you recognize these organs? I’m sure you do. These are all internal organs of the human body.
Can you put the organs in their right places in the body? That should be lots of fun.
I hope that you looked carefully at the organs and parts, as we will be checking on them later as we move along.
Which system will we look at first? Let’s look at the skeletal system first.
The Skeletal System
Touch different parts of your body – your hand, your fingers, your foot, your toes, your back, neck, head, and so on. What do you feel? Yes, bones. Do they all feel the same? These bones make up the skeletal system .The skeletal system is made up of bones, some cartilage and joints (more than one bone). Together these structures form the human skeleton. The skeleton is the hard framework of the human body around which the entire human body is built.
Look at the diagram of the human skeleton below. Look at the different bones that are there.
Do you see the different shapes and sizes of the bones? Yes, our bones are of different shapes, lengths and even textures in some cases.
Bone is a strong and rigid form of tissue. It is the weight bearing organ of human body and it is responsible for almost all strength of the human skeleton.
What really is the purpose of the skeleton? What would happen if the body had no skeleton? Interesting question, isn’t it. Discuss with your friend or sibling. The human skeleton performs some important functions that are necessary for the survival of human beings. Let’s look at some of them:
1. STRENGTH, SUPPORT AND SHAPE:
It gives strength, support and shape to the body. Without a hard and rigid skeletal system, the human body cannot stand upright, and it will become just a bag of soft tissues without any proper shape.
2. PROTECTION OF DELICATE ORGANS:
In areas like the rib cage and skull, the skeleton protects inner soft but vital organs like heart and brain from external shocks. Any damage to these organs can prove fatal, therefore the protective function of the skeleton is very important.
3. LEVERAGE FOR MOVEMENTS: Bones of the human skeleton in all parts of the body provide attachment to the muscles. These muscles provide power for producing movements of the body parts. In these movements the parts of skeleton act like levers of different types thus producing movements, according to the needs of the human body.
4. PRODUCTION OF RED BLOOD CELLS: Bones like the sternum, and heads of tibia help to produce blood cells. These are the sites where there