Articles [Nature]

Fertilization Once the pollen grains reach the stigma, each grain produces a long tube called the pollen tube. The tube, which carries the male gamete, pushes its way down through the style and into the ovule through the micro Pyle. The male...

Clouds and rain also cause changes in weather. The weather becomes cooler when it rains. In nature, water changes to water vapor due to heat. This process is known as evaporation. The water vapor cools off and this process is known as condensation....

                          It  is ironical that the world is afraid of the smallest thing that available  in the universe.It is the atom.Inspite of  its smallness it contains unbelievaable quantities of energy. this energy can be used fo good of...

Pollution Pollution is the introduction into the environment of substance that harms the health and affects the survival or activity of living organisms. Pollution can also be defined as any modification of the environment- physical, chemical or...

Unpleasant or undesirable sound is noise. The pitch of a sound means how shrill or bass it is. Sounds with a high pitch or those which are very loud are not only unpleasant, but also injurious. Prolonged exposure to loud noise can cause headache,...

Human blood can be classified into four groups, as discovered by Karl Land Steiner in 1900. Blood groups are differentiated on the basis of antigens. These antigens are groups of specific molecules produced by and found on the surface of RBCs....

Two of the problems associated with water are shortage and pollution. We will discuss the cases of water shortage under the section on conservation. In this section, we will discuss the cases of pollution of surface water bodies, ground water and...

As in the case of plants, sexual reproduction in animals begins with fertilization, which is the fusion of the sperm with the ovum are also called the egg cell or egg. In the case of amphibians and fish, the fusion of the gametes takes place...

We depend on surface water bodies and ground water to meet all needs. Despite the fact that he water cycle continually regenerates these sources of water, many parts f the world have been facing an acute shortage of water. Deforestation, overuse of...

Pollution is a major challenge of our times and is a serious threat to the very existence of mankind on this earth. The pollution of the environment has gone to such an extent that we are unable to breathe fresh air and drink fresh water. Pollution...