Question

What type of RNA has the shortest lifetime in cells?

Short answer

Short Answer: Among the three main types of RNA (mRNA, rRNA, and tRNA), mRNA has the shortest lifetime in cells. This is attributed to the cell's constant need to adjust gene expression levels, requiring the continuous synthesis and degradation of mRNA.

Step-by-step solution

Understand the main types of RNA

There are three main types of RNA: 1. mRNA (messenger RNA) - This type of RNA carries genetic information from the DNA to the ribosome, serving as a template for protein synthesis. 2. rRNA (ribosomal RNA) - This type of RNA is a structural component of ribosomes, which are the cellular machines responsible for protein synthesis. 3. tRNA (transfer RNA) - This type of RNA transfers the correct amino acid, as specified by the mRNA, to the growing polypeptide chain during protein synthesis.

Determine the function and stability of each type of RNA

Now that we understand the main types of RNA, let's discuss their functions and stability: 1. mRNA is constantly being synthesized and degraded, as it carries the genetic information required for protein synthesis. Since the demand for proteins varies depending on the cell's needs and conditions, the lifetime of mRNA is relatively short to allow for rapid changes in gene expression. 2. rRNA, as part of the ribosome, is more stable and less prone to degradation. rRNA serves as a scaffold for the ribosome and contributes to the catalytic activity of the ribosome during protein synthesis. 3. tRNA is also relatively stable. It plays a crucial role in recognizing the mRNA codons and transporting the appropriate amino acids to the ribosome for protein synthesis.

Identify the type of RNA with the shortest lifetime

Among the three main types of RNA (mRNA, rRNA, and tRNA), mRNA has the shortest lifetime in cells. This is because the cell needs to be able to rapidly adjust its gene expression levels, and therefore, mRNA is constantly being synthesized and degraded to accommodate the changing needs of the cell.