Question

The main function of an mRNA molecule is to ________ . a. store heritable information b. carry a translatable message c. form peptide bonds between amino acids

Short answer

The main function of an mRNA molecule is to carry a translatable message.

Step-by-step solution

Understanding mRNA

To solve the problem, we need to first understand what mRNA is. mRNA stands for messenger RNA, which is a type of RNA that is essential in the process of protein synthesis. It carries the instructions from DNA to the ribosome, where proteins are synthesized.

Analyzing the Options

Considering the choices given: - Option a, 'store heritable information,' describes a function more aligned with DNA, which stores genetic information. - Option c, 'form peptide bonds between amino acids,' is a function of rRNA and tRNA which assist in protein synthesis at the ribosome. - Option b, 'carry a translatable message,' describes the role of mRNA, which carries the transcribed genetic code from the DNA to the ribosomes for translation into proteins.

Selecting the Correct Function

Having analyzed each option, option b, 'carry a translatable message,' best describes the function of mRNA. It is responsible for providing the genetic instructions that are translated into a sequence of amino acids during protein synthesis.

Key concepts

Protein Synthesis

Protein synthesis is a biological process that enables our cells to make proteins, which are essential for various cellular functions. This process occurs in two main stages: transcription and translation. During transcription, a specific segment of DNA is copied into messenger RNA (mRNA). This crucial first step takes place in the cell nucleus. The newly formed mRNA carries the genetic instructions needed to make a protein from the DNA to the ribosomes, the cell's protein factories.

Once the mRNA reaches the ribosome, translation occurs. Here, the ribosome reads the sequence of the mRNA three nucleotides at a time. These three-nucleotide sequences are called codons, and each codon corresponds to a specific amino acid, the building blocks of proteins.

• Step 1: Transcription - DNA to mRNA
• Step 2: Translation - mRNA to Protein

This coordinated process ensures that proteins are built accurately and efficiently, fulfilling their roles within the cell.

Messenger RNA

Messenger RNA, commonly known as mRNA, plays a central role in converting the genetic information stored in DNA into functional proteins. It acts as a bridge, transmitting the genetic instructions from the DNA in the cell nucleus to the ribosomes in the cytoplasm.

mRNA is synthesized during the transcription phase of protein synthesis. During this process, mRNA is generated as a complementary strand to a template strand of DNA. Once formed, this mRNA molecule exits the nucleus through the nuclear pore and enters the cytoplasm, providing the template necessary for the assembly of a protein.

The integrity and sequence of the mRNA are vital. Any errors can lead to dysfunctional proteins, potentially causing genetic disorders or diseases. The role of mRNA is not just passive; it works actively with other cellular components to ensure the precise production of proteins according to cellular needs.

Genetic Code Translation

Genetic code translation is a fascinating part of protein synthesis where the genetic code contained in mRNA is decoded to build a protein. This translation process takes place in the ribosomes, which read and interpret the mRNA codons.

Each group of three bases on the mRNA, known as a codon, codes for a specific amino acid. The sequence of codons determines the sequence of amino acids in the protein being synthesized. Transfer RNA (tRNA) molecules help facilitate the translation by carrying the appropriate amino acids to the ribosome.

Important components of genetic code translation include:

• Codons: The three-base sequences on mRNA that determine each amino acid.
• tRNA: These molecules match the correct amino acids with each codon, ensuring the right protein structure is formed.
• Ribosomes: The molecular machines where protein synthesis occurs, ensuring the mRNA is read correctly and efficiently.

By accurately translating the genetic code, cells are able to produce proteins necessary for life, each with a specific function dictated by the sequence of amino acids.