Word Bank Anticodon Codon Cytoplasm
Exons Introns Messenger
Nucleus Protein Ribosomal
Ribosome Ribosome RNA polymerase
Transcription Transfer Translation

2. The first step of protein synthesis is . This step occurs in the of the cell. During this step the enzyme makes a copy of a gene out of RNA. This is called a RNA or mRNA. Some parts of mRNA called have to be cut out because they are not part of the code for the final protein. This is called mRNA splicing. The remaining parts which do code for the protein being built are called . 3. The second step of protein synthesis is . This step occurs in the of the cell. During this step the mRNA is used by a to build a polypeptide. Every three bases of the mRNA are called a and code for one amino acid in the polypeptide. 4. Ribosomes are made up of a large subunit called 50S and a small subunit called 30S. These subunits are made out of two types of organic macromolecules: and RNA or rRNA. 5. RNA or tRNA bring the amino acids to the . One end of each tRNA is attached to an amino acid and the other end is made up of three nucleotides, the bases of which form a triplet called an . This region recognizes its complementary sequence (codon) on the mRNA so that its amino acid can be added in the correct order.