Final answer:
The genetic code within an organism's DNA determines its traits by specifying the build of proteins, which are vital for its structure and function. Genes encode for specific proteins that, when expressed, lead to the observable characteristics (phenotype) of the organism.
Step-by-step explanation:
Organisms have a genetic code within their DNA that determines their traits. This code is a sequence of nucleotides that specifies which amino acids will be used to build proteins. Proteins are essential for the structure, function, and regulation of an organism's cells, tissues, and organs. Each gene in the DNA sequence encodes a particular protein, with the sequence dictating the order of amino acids in the protein. This process is guided by the central dogma of molecular biology, which states that DNA is transcribed into messenger RNA (mRNA), and the mRNA is then translated into a protein.
A gene's expression, which leads to protein synthesis, can result in a distinct phenotype, which are the observable characteristics of an organism. The genotype, or the collection of genes of an organism, along with environmental interactions, determines the phenotype. Thus, through the production of proteins encoded by genes, cells use genetic information to give rise to an organism's traits.