Define heredity. Explain the mechanism of hereditary changes.

Heredity is the transfer of characteristics from one generation to the next via genes or from parent to the offspring. Due to heredity offspring look like their parents. Examples cats give birth to kittens and cow give birth to calves.

The mechanism of heredity changes:

•DNA carries genetic information in genetic codes. The information codes for various proteins.

•These proteins interact with the environment forms various types of living organisms.

•By a complex process DNA under goes replication or duplication. Recombination of DNA segment during meiosis and sudden change in DNA (mutation) makes various new forms of life.

•All organisms, from the simplest bacteria to the largest eukaryotes, use DNA as the main form of heredity.

•Before the role of DNA was understood, it was well known that some mechanism caused offspring to resemble the parents.

•Children look like their parents have visible characteristics that pass from one generation to the next.

•The first scientist was Gregor Mendel, in the 1800s. He proposed the idea that each organism carries a pair of factors which transfer from parent to offspring. Today, we call these factors as genes.