What are corals?

Corals are small colourful marine animals that are found in the seas. They build the coral reefs. Their exoskeletons provide the structure of the reefs. The reefs are of high ecological importance. Corals grow very slowly at the rate of about one centimetre a year.

• • •

How much skin do humans shed?

Our skin is made of many layers of cells. The outer layer is flaky and the inner layers have structure giving and nourishing elements. The outer skin gets dry or damaged with time and so it gets shed. An average person sheds about 30,000 cells every minute and about 18 kilograms of skin in his or her lifetime. Most household dust is made of dead skin.

• • •

The first synthetic human chromosome

Chromosomes are considered the basic structures of heredity. They carry the codes that give rise to the expression of the characteristic features of an organism. Humans have 46 chromosomes. In 1997, a team of scientists J.J. Harrington, G.V. Bokkelen, R.W. Mays, K. Gustashaw, and H.F. Willard synthesized artificial chromosomes. These chromosomes are stable up to six weeks. These chromosomes can be used as vectors to carry genes of interest into other cells and for the study of their expression.

• • •