what kind of different kinds does it have?
Classical Mendelian inheritance, cellular biology, molecular biology, biochemistry, and biotechnology
Molecular genetics
The field of study is based on the merging of several sub-fields in biology: classical Mendelian inheritance, cellular biology, molecular biology, biochemistry, and biotechnology. 
when are organisms considered to belong to the same species When two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction what is it classified as? UNANSWERABLE what is the main topic defined as? Biologists and taxonomists have made many attempts to define species, beginning from morphology and moving towards genetics what are the historical notes for the last word above? The observation that living things inherit traits from their parents has been used since prehistoric times to improve crop plants and animals through selective breeding name it's different kinds? Molecular genetics, epigenetics and population genetics what is the first kind of it? It is a sub-field of biology that addresses how differences in the structures or expression of DNA molecules manifests as variation among organisms
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Molecular genetics [SEP] Introduction
Molecular genetics is a sub-field of biology that addresses how differences in the structures or expression of DNA molecules manifests as variation among organisms. Molecular genetics often applies an "investigative approach" to determine the structure and/or function of genes in an organism's genome using genetic screens. The field of study is based on the merging of several sub-fields in biology: classical Mendelian inheritance, cellular biology, molecular biology, biochemistry, and biotechnology. Researchers search for mutations in a gene or induce mutations in a gene to link a gene sequence to a specific phenotype. Molecular genetics is a powerful methodology for linking mutations to genetic conditions that may aid the search for treatments/cures for various genetics diseases.