ORGANISATION OF LIFE
After the completion of this lesson, students will be able to:‹‹
* understand the different levels of organization seen in the animal world.
* know about the structure of cells.
* understand the types of tissues.
* know about the structure of eye as an example for organ level of organization.
*understand the respiratory system as an example for system level of organization.
* understand the physiological functions of organizational setup with reference to homeostasis, diffusion, osmosis, osmoregulation, cellular respiration and metabolism.
If you look around your sorrounding, you will be able to observe numerous varities of animals. There are animals like amoeba which cannot be seen by our naked eye. There are also animals like elephants and blue whale which are of huge size. The variations in animal are not only seen in size but also in the complexity of the cells, tissues and the body structure.
Based on the structural organization, organisms can be classified into prokaryotes and eukaryotes. In some organisms like bacteria, cyanobacteria and mycoplasma, the true nucleus is absent. These organisms are called prokaryotes. However, organisms like plants and animals have cells with a well-defined nucleus covered by membrane. These organisms are called eukaryotes. Some organisms have a single cell body and they are called as unicellular organisms. Eg. Yeasts and amoeba. Organisms such as plants, animals and human beings are made of a large number of cells and they are called multicellular organisms. In this lesson, let us learn about different levels of organizations of living organism with suitable example.