Final answer:
A tRNA molecule with an amino acid attached is known as a charged tRNA. This charging is done by enzymes called aminoacyl tRNA synthetases. Even with modification, a charged tRNA's anticodon will still recognize its corresponding mRNA codon. Option 1.
Step-by-step explanation:
A tRNA that has an amino acid attached is called a charged tRNA. This process of attaching an amino acid to a tRNA molecule is known as tRNA charging.
Each tRNA molecule is linked to its correct amino acid by a group of enzymes called aminoacyl tRNA synthetases.
The anticodon of the tRNA is designed to match the codon on the mRNA; therefore, if the tRNA is chemically modified to carry a different amino acid than the one specified by its anticodon, it will still recognize and bind to the codon in the mRNA that matches its anticodon.
It is the responsibility of the aminoacyl tRNA synthetases to ensure the correct amino acid is attached, which is a part of the 'second genetic code'. Option 1.