Question

Observe the illustration and answer the following questions.
(a) Identify the molecule labelled as ‘X’.
(b) Mention its role in protein synthesis.

Hint:

mRNA = messenger RNA → carries genetic code from DNA to ribosome for protein formation.

Answer 1

Step 1: Understanding the diagram.
The diagram shows the process of transcription inside the nucleus, where a DNA strand is used as a template to form a complementary RNA strand. The labelled part ‘X’ represents the RNA molecule leaving the nucleus.
Step 2: Identification of molecule ‘X’.
The molecule labelled ‘X’ is messenger RNA (mRNA). It is synthesized from DNA during transcription.
Step 3: Role of mRNA in protein synthesis.
mRNA carries the genetic information (in the form of codons) from DNA in the nucleus to the ribosomes in the cytoplasm.
Step 4: Function during translation.
At the ribosome, mRNA serves as a template for assembling amino acids in the correct sequence to form a protein. Each codon on mRNA corresponds to a specific amino acid.
Step 5: Conclusion.
Thus, mRNA acts as a messenger that transfers genetic information from DNA to ribosomes, enabling protein synthesis.