• There has been life on earth for over 3.5 billion years.
• There are around 30 million species of animals and plants in the world.
• There is a dynamic relationship between the world of life and the inanimate world.

• Systems within the body  are interconnected in the way their structure is related to function.

• Natural resources are limited on Earth
• With the current increase in growth of human population there is a threat of depletion of natural resources.

1. Destruction / Depletion of Ozone layer  in the atmosphere,
2. Acid rain 
3. Global warming caused by increasing concentrations of CO2 in the atmosphere
4. Pollution of rivers and underground water supplies leading to a dearth in drinking water in the future

• With the current rate of population growth, three people are added to the world’s population
  each second.
• The current human population of 6 billion is expected to double in less than 40 years.
• Therefore, for the survival of mankind, sustainable food production is necessary.

1. Production of high yielding varieties of plants and animals
2. Development of disease resistant varieties
3. Improved methods of post harvest technology needs  to be emphasized.

• Scientists are currently working on cures for diseases such as cancer, AIDS, malaria and
  TB.
• AIDS is a serious and growing health problem worldwide.
• Malaria can kill over 3 million people per year in underdeveloped countries.
• Cancers which is the leading cause of death in some countries are not fully understood yet.
• In addition, new diseases arise from time to time.

Scientists are working on prevention, remedial measures and cures for diseases.