look at the picture!

The organism's genotype encodes their phenotype because the genotype corresponds to the characteristic that is determined by genes —formed by fragments of DNA— which are transcribed into mRNA to be translated into amino acid sequences in the synthesis of proteins, determining the morphological and functional characteristics of an organism, that is, its phenotype.

Explanation:

Genotype corresponds to the genetic information contained in the DNA, according to the sequence of nucleotides in its molecular structure. This genotype includes characteristics or polymorphisms that define the appearance and function of living beings.

Each DNA molecule constitutes a chromosome, formed by genes —DNA fragments— each of which determines specific characteristics.

When DNA is transcribed into mRNA, information is being sent that is necessary for the incorporation of amino acids into a protein that is being synthesized. The proteins, in turn, determine morphological and functional characteristics that constitute the phenotype of an individual.