How do genes determine the traits of an organism?

The genes, which are part of DNA, contain the genetic information inherited from the parents determine the traits of an organism.

The ‘complete set of all the genes and the DNA’ is called the genome which stores the entire set of information of how an organism is structured and maintained.

The pattern of dominant and/or recessive traits and the genetic variations are determined by the allelles.  

Explanation:

The genetic codes in the genes represent the particular amino acid codes and their linkages specific to particular protein.  The amino acids link together to form long polypeptide chains of protein molecules.  

These proteins determine various traits through various roles like:

Messenger proteins: Hormones like insulin, estrogen etc., control and coordinate various functions of the body

Pigments: Like melanin determines the color of the hair, skin, eyes.

Structural protein: Like keratin gives structure of hair, nails; myosin determines muscle structure

Antibodies: Determine the immunity of a person

Ion channel proteins, messenger proteins, structural proteins, receptor proteins etc.: Determine various physiological traits.

igneous rocks are formed by solidification of cooled magma (molten rock), with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks.  

the composition depends on the source magma. there are almost a thousand types of composition found till now.  

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