1. Ribosomes and Transfer RNA
Natalia Sivackova

2. All tRNA Molecules Have…
Sections that become double stranded by base pairing
A triplet of bases called the anticodon, in a loop of seven bases
Two other loops
The base sequence CCA at the 3’ terminal

3. tRNA Activating Enzymes
The base sequence of tRNA molecules varies and this causes some variable features in structure:
An extra small loop is sometimes present
The base paired sections are sometimes helical
Gives tRNA distinctive 3-D shape
Distinctive chemical properties
 Allows the correct amino acid to be attached by tRNA activating enzyme

4. tRNA 20 different tRNA activating enzymes
tRNA activating enzyme recognizes tRNA molecules by shape and chemical properties
ATP is needed for attachment of amino acids

5. Structure and Function of Ribosomes
Protein and rRNA both for part of the structure of ribosomes
2 subunits: one large, one small
3 binding sites for tRNA on the surface of the ribosome
2 tRNA molecules can bind at the same time to the ribosome
There is a binding site for mRNA on the surface of the ribosome

6. Peptide Bonds Ribosomes are the site for polypeptide synthesis
= linking amino acids together by a condensation reaction

7. Vocabulary tRNA activating enzyme Free ribosomes Bound ribosomes
REFERENCES:
Study Guide pg. 63
HL book pg.

8. Bibliography