Question

How does the genotype of a bacterium determine its phenotype? Use the terms gene, mRNA, ribosome, and polypeptide in your answer.

Answer 1

The genotype of a bacterium, composed of all its genes, determines its phenotype through the processes of transcription and translation, which convert gene information into functional polypeptides within the ribosome, forming the basis for observable characteristics.

Step-by-step explanation:

The genotype of a bacterium is the entirety of its genetic information, including all the genes comprised of DNA. This genotype dictates the organism's phenotype, or observable characteristics, through a process known as the Central Dogma of molecular biology. This process involves the conversion of genetic information from DNA to messenger RNA (mRNA) during transcription. The mRNA then travels to the ribosome, where translation occurs, leading to the assembly of a chain of amino acids called a polypeptide. Each gene on the DNA sequence corresponds to a specific polypeptide, and it is the expression of these polypeptides that ultimately results in the phenotype of the bacterium.

For example, if a bacterium possesses a gene coding for an enzyme that digests a certain sugar, the presence of that sugar in the environment can trigger the transcription of that gene into mRNA. The mRNA is decoded by the ribosome to produce the enzyme, which becomes part of the phenotype of the bacterium. Gene expression is a regulated process, ensuring that proteins are synthesized only when needed, allowing for different phenotypes to arise from the same genotype in response to environmental conditions.

Answer 2

Typically, the genotype is encoded in the DNA by the gene; this gene in the DNA will then undergo the process of transcription and the information in the gene will be transcripted into mRNA. The mRNA will then undergo the process of translation and the information in the mRNA will  be translated into a polypeptide chiefly by the action of ribosome. Thus, bacteria with different genotypes will have different protein which automatically means that they will have different phenotypes.