[CBSE AIPMT 1997]
Correct Option (b)
Reason : tRNA (soluble RNA = sRNA) is a 70-75 nucleotide long molecule. 80% of this RNA is double helical, one end of this molecule has G and other C-C-A sequences.
The clover leaf model (2D) of tRNA was given by R Holley (1968) and Kim et al, (1973) suggested 'L' shaped model (3D) of tRNA by X-ray diffraction while studying phenyl alanine tRNA of yeast. Each amino acid had its own specific tRNA molecule which transfers it from cytoplasm to the ribosome.