GENETICS
Each person is unique,but he or she also inherits some characteristics and even appearence from his or her parents.The study of how chrecteriswtics are passed on from parents to off spring is known as Genetics.and it affects all forms of life .At the centre of the process is the deoxiribonucleic acid(DNA) molecules,which exist inside every living celland contains a complex chemical ''Code" that controls the way in which life forms are put together and operate.DNA,in turn,makes up chromosomes. all of these microscopic structures live in the nuclei of cells.
CHROMOSOMES
A chromo some is a thread-like structure found in the nucleus of a cell.Chromosome storen DNA and carry DNA molecules when a cell reproduces by dividing.Most human cells contain 46 chromosomes, divided into 23 pairs;23 chromosomes are derived from the each of the parents.
GENES
A gene is the basic physical and functional unit of heredity. Genes, which are made up of DNA, act as instructions to make molecules called proteins. In humans, genes vary in size from a few hundred DNA bases to more than 2 million bases.
Geno type and phenotype The Genotype is the overall genetic blue print for an organism.The Phenotype is what an organism actually looks like ,baced on genotype and environment.
Alleles
Each gene has two or more forms called Alleles.They control the same characteristics but different versions for it.
DNA
Deoxyribonucleic acid is a molecule that carries most of the genetic instructions used in the development, functioning and reproduction of all known living organisms and many viruses.
The discovery of the DNA molecules was a collaborative effort.Ronald Franklin (1920-58) completed ground work,which was consolidated in 1953 by Francise Crick,James Watson and Maurice Wilkins,and they shared 1962 nobel price.
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