What is present on the 3' end of all functional, mature tRNAs?
5' end of the tRNA is always base paired, and 3' end is free or attached to an amino acid. 3' end of all the tRNA ends with the same sequence, i.e. CCA. This trinucleotide sequence is post-transcriptionally added to the tRNA by the enzyme CCA tRNA nucleotidyl transferase.
The cloverleaf loop
The anticodon
The sequence 5'CCA3'
The codon
Transcription