NCERT Book Class 9 Science Why Do We Fall Ill

WHY DO WE FALL ILL

Activity _____________13.1

• We have all heard of the earthquakes in Latur, Bhuj, Kashmir etc. or the cyclones that attack the coastal regions. Think of as many different ways as possible in which people’s health would be affected by such a disaster if it took place in our neighbourhood.

• How many of these ways we can think of are events that would occur when the disaster is actually happening?

• How many of these health-related events would happen long after the actual disaster, but would still be because of the disaster?

• Why would one effect on health fall into the first group, and why would another fall into the second group?

When we do this exercise, we realise that health and disease in human communities are very complex issues, with many interconnected causes. We also realise that the ideas of what ‘health’ and ‘disease’ mean are themselves very complicated. When we ask what causes diseases and how we prevent them, we have to begin by asking what these notions mean.

We have seen that cells are the basic units of living beings. Cells are made of a variety of chemical substances – proteins, carbohydrates, fats or lipids, and so on. Although the pictures look quite static, in reality the living cell is a dynamic place. Something or the other is always happening. Cells move from place to place. Even in cells that do not move, there is repair going on. New cells are being made. In our organs or tissues, there are various specialised activities going on – the heart is beating, the lungs are breathing, the kidney is filtering urine, the brain is thinking.

All these activities are interconnected. For example, if the kidneys are not filtering urine, poisonous substances will accumulate. Under such conditions, the brain will not be able to  think properly. For all these interconnectedactivities, energy and raw material are needed from outside the body. In other words, food is a necessity for cell and tissue functions. Anything that prevents proper functioning of cells and tissues will lead to a lack of proper activity of the body. It is in this context that we will now look at the notions of health and disease.

13.1 Health and its Failure

13.1.1 THE SIGNIFICANCE OF ‘HEALTH’

We have heard the word ‘health’ used quite frequently all around us. We use it ourselves as well, when we say things like ‘my grandmother’s health is not good’. Our teachers use it when they scold us saying ‘this is not a healthy attitude’. What does the word ‘health’ mean?

If we think about it, we realise that it always implies the idea of ‘being well’. We can think of this well-being as effective functioning. For our grandmothers, being able to go out to the market or to visit neighbours is ‘being well’, and not being able to do such things is ‘poor health’. Being interested in following the teaching in the classroom so that we can understand the world is called a ‘healthy attitude’; while not being interested is called the opposite. ‘Health’ is therefore a state of being well enough to function well physically, mentally and socially.

Please refer to attached file for NCERT Class 9 Science Why Do We Fall Ill