Information that encodes certain functional products called PROTEIN are present in the DNA molecule. However, the information needs to be expressed via the processes of transcription and translation. Transcription is the synthesis of a mRNA using a DNA template.
The mRNA then undergoes translation, where it is read in a group of three nucleotides called CODON. Each CODON specifies a particular amino acid. Due to the degenerate nature of the genetic code, more than one codon can specify one amino acid.
Hence, in the case of phenylalanine amino acid, codons UUU and UUC both specify it. This means that whenever UUU and UUC are read during translation, a phenylalanine is added to the peptide chain.
If the child has blood type OO and his mothes has AO type, the father must have O in his genotype: A(AO), B(BO), O(OO). The male phenotype AB exclueds him as father.
