the overall goal of gene expression is to make a structural protein that can be used by the cell a copy of the gene that can be used by the cell mRNA that can be passed on to the next Generation a copy of the gene that can be passed to the Next Generation
The Correct Answer and Explanation is:
Correct Answer:
A copy of the gene that can be used by the cell.
Explanation
Gene expression is the process by which the information encoded in a gene is used to produce a functional product, typically a protein. The overall goal of gene expression is not simply to copy genetic material for inheritance (as in DNA replication), but rather to utilize the genetic code to build molecules—mostly proteins—that the cell needs to function.
Gene expression occurs in two main steps: transcription and translation. During transcription, the DNA sequence of a gene is copied into messenger RNA (mRNA). This mRNA is a temporary, working copy of the gene that carries the instructions from the DNA in the nucleus to the ribosomes in the cytoplasm. In translation, the ribosomes read the mRNA sequence and assemble the appropriate amino acids to build a protein.
These proteins may serve a variety of cellular roles, such as enzymes, structural components (like actin or tubulin), signaling molecules (like hormones), or transporters (like hemoglobin). Therefore, the ultimate purpose of gene expression is to produce proteins that allow the cell to maintain its structure, carry out metabolic functions, respond to its environment, and grow or divide as necessary.
Some confusion may arise because DNA replication (which does make copies of genes) occurs before cell division, ensuring genetic information is passed to the next generation of cells or organisms. However, this process is distinct from gene expression.
Similarly, while mRNA is a product of gene expression, it is not passed on to the next generation, as it is a temporary molecule quickly degraded after use. The mRNA’s purpose is to enable protein synthesis, not heredity.
In summary, gene expression serves the cellular, functional need of producing proteins, not the hereditary need of passing DNA to offspring. Thus, the correct answer is: a copy of the gene that can be used by the cell.
