Final answer:
True, DNA contains the genetic code necessary for the correct sequence of amino acids in protein synthesis. The code is translated from DNA to mRNA and then to proteins, with each cell type expressing only the necessary proteins for its functions. The genetic code is nearly universal, assigning codons to specific amino acids across all living organisms.
Step-by-step explanation:
True, DNA must have the information that directs the correct order of amino acids to form proteins. DNA contains the genetic code, which is essentially a set of instructions for assembling amino acids in a specific order to create proteins. This sequence of amino acids determines a protein’s structure and function. The process begins with the transcription of DNA to messenger RNA (mRNA), where the code in DNA is copied. Subsequently, during translation, the mRNA is read in sets of three nucleotides known as codons, each of which specifies a particular amino acid.
It’s important to note that not every gene is constantly expressed. Gene expression refers to the process by which the information from a gene is used to synthesize a functional gene product, usually a protein. This expression can be regulated, meaning that each cell type only "turns on" the genes necessary to produce the proteins required for its function.
Moreover, the genetic code is nearly universal, with all living organisms using the same code. Each of the 64 codons encodes one of the 20 standard amino acids, except for the stop codons which signal the end of a protein sequence. However, one codon can sometimes encode for more than one amino acid and the same codon encodes for the same amino acid across different species like humans and plants.