What is Genetics? – Definition
Genetics is a branch of biology which studies heredity and variation. Scientists those study heredity, variation are called geneticists. The term genetics was coined by W. Bateson.
What is Heredity? – Definition
Heredity is the transfer of characters from parents to offspring generation after generation and hence responsible for biological similarity between them.
It is the heredity because of which progeny is similar in various characters to either of its parent. This phenomenon by which progeny retains characters from parents is named as inheritance.
What is Variation? – Definition
Variation is the difference among the parents and offspring of these parents.
Variation observed, can be because of two main reasons. So it is of two types based on these reasons.
- Hereditary variation
- Environmental variation
Only hereditary variations are transferred to progeny. Environmental variations belong to that generation only. These are not carried to the next generation.
History of Genetics
History of genetics is can be summarized with respect to Mendel’s work. Scientists and their findings can be grouped according to their time period as follows.
- Pre – mendelian
- Mendelian Period
- Post – mendelian