How do the unusual bases of the loops in tRNA influence tRNA structure?

a. They disrupt hydrophobic interactions in the loop regions causing the loops to form.

b. They bind to proteins that hold the loops open.

c. They disrupt H bond formation which causes complementary pairing in the stem regions.

d. They prevent van der Waals interactions which prevents loop formation.

e. They disrupt H bond formation in the loop regions causing the loops to form

The greatest variability among codons specifying the same amino acid occur _________.

a. in the middle nucleotide of the triplet

b. in the first and third nucleotides of the triplet

c. in the first two nucleotides of the triplet

d. in the third nucleotide of the triplet

e. in the last two nucleotides of the triplet

The initiator tRNA enters the 30S ribosomal subunit at the ____ during prokaryotic protein synthesis.

a. A site

b. E site

c. Q site

d. P site

e. 50S attachment point

All three major types of RNA (mRNA, tRNA and rRNA) are processed before they are mature. They are derived from precursor RNA molecules that are considerably longer than the final RNA product. These precursor RNAs are called _________.

a. a and b

b. pre-RNAs

c. primary transcripts

d- predominances

e. prions