Levels of Organization:

The levels of biological organization range from atoms and molecules, to cells, tissues, organs, organ systems, organisms, populations, communities, ecosystems, and finally, the biosphere, which includes all living things on Earth.These levels are as follows:

Atomic Level of Organization:

All matter is made up of elements, which are composed of atoms. Each atom is made up of subatomic particles, such as electrons, protons and neutrons. In nature, there are more than 100 kinds of elements and among these 16 elements are called bio-elements, which are vital for life. Only six elements such as C, H, O, N, S and P are called the basic elements of life.

Molecular Level of Organization:

Molecules are formed by the binding of atoms. These organic molecules of cells are called biomolecules. They are constructed in great variety and complexity. They are classified as macromolecules and macromolecules.

Glucose, amino acid and fatty acids are macromolecules, whereas carbohydrates, proteins and lipids are macromolecules. The units of macromolecules combine to form biomolecules.

Cellular Level of Organization:

The biomolecules, when working together in the form of suspension, are called Protoplasm. Protoplasm is the combination of organic and specific inorganic substances. When a protoplasm works in the form of a unit, it is called a cell. A cell is the basic unit of living organisms when similar types of cells organize together in a group, they are called tissues. The different types of tissues arranged in a particular manner to work together are called organs.

Organs of different type work in a coordinated manner to perform a function which is called an organ system. When different organ systems function in coordination as a unit, they form a body or Multicellular Organism.

Taxonomic Level:

There is another level of organization that is related to living organisms. The species is the smallest unit of the taxonomic level of organization, which includes morphologically similar living organisms which interbreed and produce fertile offspring.

Population Level:

All the members of a species, living in specific habitats are called the “Population”. A group of parrots living in a tree is called a parrot population.

Community Level:

The members of different species, living in specific habitats are called a community. A group of different kinds of birds, living in a tree, is called a bird community.

Ecological System:

Communities always depend on their non-living environment in reciprocal interaction for their survival. For example, oxygen for respiration is obtained from the environment and CO2 is given out. This interaction is called an ecosystem or an ecological system.

Biosphere Level:

The part of the earth where life exists is called the biosphere. It consists of different kinds of ecosystems.

Cell Organization:

In living organisms, the cell organizes in three ways to form the bodies of organisms: Unicellular colonial, and multicellular organizations. The organisms formed through these organizations are unicellular, colonial, and multicellular organisms, respectively.

1. Unicellular Organization:

In unicellular organisms, only one cell carries out all life activities.

For Example:

Amoeba, Paramecium and Euglena

Amoeba:

Amoeba is a unicellular organism found in shallow ponds, pools, and stagnant water.
Its size is about 0.25 millimeters.
It has an irregular shape.
It has a cell membrane which helps in the movement of molecules and protects cytoplasm.
The outer part of the cytoplasm is clear and transparent and called ectoplasm.
While the inner part of the cytoplasm is called the endoplasm (sol).
The cytoplasm contains a nucleus, food vacuoles, mitochondria etc.
Amoeba moves by false foot, called pseudopodia (plural is Pseudopods).

2. Colonial Organization

In the colonial type of cellular organization, many unicellular organisms live together but do not have any division of labor among them. Each unicellular organism is a colony that lives its own life and does not depend on other cells for its vital requirements. Volvox, a green alga found in water, is an example of a colonial organization. Hundreds of volvox cells make a colony.

For Example:

Volvox:

Volvox is a type of green alga that lives together in a colony.

Each volvox cell has two flagella. The flagella beat together to propel the colony into water.

Volvox cells have chlorophyll and make their food by photosynthesis.

Volvox is not harmful to humans because it does not produce any toxic substance.

3. MULTICELLULAR ORGANIZATION

In multicellular organization, cells are organized into tissues, organs and organ system.

For Example:

The part of the earth where life exists is called the biosphere. It consists of different kinds of ecosystems.

Mustard Plant:

SCIENTIFIC NAME: Brassica campestris

1. Sowing:

It is sown in winter and produces seed at the end of winter.

2. Importance:

Its plant body is used as a vegetable, and its seeds are used for extracting oil.

3.Body Parts:

The plant body consists of two main parts.

4.Vegetative Parts:

It includes roots, branches and leaves. These do not take part in sexual reproduction.