What is Translation _ It’s Meaning and Definition A step in protein biosynthesis where a genetic.

What is Translation _ It’s Meaning and Definition A step in protein biosynthesis where a genetic.

What is Translation? – Meaning and Definition

Translation in Biology:

Translation is a process in protein biosynthesis where the genetic code carried by mRNA (messenger RNA) is decoded to produce a specific sequence of amino acids, which forms a protein. This process occurs in the ribosomes of the cell.

 Where Does Translation Occur?

• In prokaryotic cells (like bacteria): Occurs in the cytoplasm because they lack a defined nucleus.
• In eukaryotic cells (like humans): Takes place in the cytoplasm on ribosomes, which may be free or attached to the endoplasmic reticulum (ER).

 Steps of Translation:

1. Initiation:

   • The mRNA attaches to the ribosome.
   • The start codon AUG (which codes for methionine) is recognized.
   • The tRNA with the complementary anticodon carries the first amino acid (methionine).

2. Elongation:

   • The ribosome moves along the mRNA, reading codons.
   • tRNA brings the appropriate amino acid, and a peptide bond is formed between amino acids.
   • This process continues, elongating the polypeptide chain.

3. Termination:

   • The process ends when a stop codon (UAA, UAG, UGA) is encountered.
   • The polypeptide chain is released, and the ribosome disassembles.

 Key Components in Translation:

• mRNA (Messenger RNA): Contains the genetic code.
• tRNA (Transfer RNA): Carries amino acids to the ribosome.
• rRNA (Ribosomal RNA): Part of the ribosome, catalyzes peptide bond formation.
• Amino Acids: Building blocks of proteins.
• Ribosome: The site of protein synthesis.

 Importance of Translation:

• Protein Synthesis: Forms the proteins essential for the structure and function of cells.
• Gene Expression: The final step in gene expression, determining traits and functions.
• Cell Growth and Repair: Proteins produced help in cell growth, repair, and regulation.

 Example of Translation:

Suppose the mRNA sequence is:
AUG UUC GAC UGA

• AUG: Start codon (Methionine)
• UUC: Phenylalanine
• GAC: Aspartic acid
• UGA: Stop codon
  Protein Sequence: Methionine – Phenylalanine – Aspartic acid

If you need a more detailed explanation or have any questions, feel free to ask!

What is Translation _ It’s Meaning and Definition A step in protein biosynthesis where a genetic.

Transcription, Translation & Protein Synthesis

UNIT 14 PROTEIN BIOSYNTHESIS

The Genetic Code & Translation