Question

What is called the science of heredity and variation?

Answer 1

Hint: The science of heredity and variation deals with studying the inheritance patterns, evolution, mutation and all the things happening inside the DNA. Heredity determines the characteristics that are transferred from parents to offspring through the genetic material. It defines the physical characters as well as genetic potential of the living organism. Variations are also passed from generations to generations through heredity.

Complete explanation:
The science of heredity and variation is known as genetics. Genetics is the study of structure, function, variation and distribution of genes. It also deals with studying the disorders in the gene. Genetics has given rise to a number of subfields like molecular genetics, epigenetics and population genetics. In genetics all the three domains of life- eukarya, bacteria, archaea are studied.
Gregor Mendel was the first person to study genetics scientifically. He studied trait inheritance patterns in the pea plant. He observed that traits are passed down from parents to offspring through units of inheritance. The unit of inheritance refers to a gene.
He proposed the law of segregation and principle of mendelian inheritance. According to Mendel’s law “When two organisms reproduce sexually, their offspring inherit one of the two alleles from each parent”. This law forms the basis of heredity.

Note:
Variation refers to the differences between biological species. The genotypic constitution produced from genes, chromosomal recombination, and linkage all contribute to the variation. It forms the root of biological evolution and breeding. The main sources of genetic variation include mutation, combination of genes during sexual reproduction and environmental factors. Environmental variation occurs mainly for species survival. It can be clearly noted in plants.