A segment of dna that codes for the ability to make one type of protein molecule is know as an

Gene

Explanation:

A GENE is the unit of inheritance in virtually the cells of all living organisms. It is a segment of DNA that codes for the ability to make one type of protein molecule. In other words, a gene encodes the synthesis of amino acids, which are building blocks of protein.

Genes are naturally found on chromosomes on which they undergo expression i.e. from gene - MRNA (transcription), from mRNA - protein (translation). Hence, based on the question asked, the segment of DNA that carries instructions for protein synthesis is called a GENE.

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