The Kingdom Protista includes diverse kinds of predominantly water-dwelling unicellular eukaryotic microorganism. Protists, like Monerans, have an immense reproductive potential. In an optimal environment, they may reproduce several times a day. This is mainly by asexual reproduction, using the process of mitosis. However, they also reproduce sexually. Continue reading Sexual Reproduction – An Important Innovation of the Early Protists.
In 1868, T. H. Huxley described protoplasm as the “physical basis of life”. Protoplasm is a clear, colorless and jelly-like substance which seemed to make up the contents of the cell. It was also described as “substance of life” or “living material”. Continue reading What is the physical basis of life?
Fifty years ago people believed that the war of humankind against the infectious diseases was virtually over and science had won over infectious diseases such as pneumonia, whooping cough, polio and small pox with the help of antibiotics, vaccines, and some aggressive public health campaigns.
It is a well-known fact that DNA acts as a genetic material in most of the organisms on this planet earth. However, it is also clear that RNA also acts a genetic material, but only in some viruses (for example, Tobacco Mosaic Viruses, QB Bacteriophage, etc.).
Continue reading Why Nature Preferred DNA over RNA?