Page 65 - The Miracle in the Cell

HARUN YAHYA
ribosomes-the cell's main production units. The ribosomes read the
instructions, starting from the beginning of the RNA strand. Each code
in the DNA is made up of three bases called a codon, and represents
one amino acid in the protein chain.
- Using the order it has obtained from the RNA, the ribosome
joins together the amino acids to form a chain.
- One by one, the amino acids are brought to a molecule called
the transfer RNA, or tRNA. Every tRNA carries its own special amino
acid. The tRNA carries the amino acid on one end and on the other, the
code with the address where the tRNA will deposit its load (the anti-
codon; Figure 3.2).
- The tRNA that arrives at the ribosome aligns along the mRNA
transcript at the described
address. There it deposits
the amino acid it is carrying Growing Ribosome
mRNA polypeptide
and moves away from the chain subunits
released
ribosome. The ribosome
moves one codon (three START STOP
COMMAND COMMAND
bases) along the mRNA
transcript. Another tRNA
molecule arrives at the new Protein produc-
tion is complete.

4. The bond between the first 5. The ribosome 6. A peptide bond is again formed
tRNA carrying the start codon moves one step along the between the second and third
and the amino acid is broken. mRNA transcript. The amino acids. The ribosome shifts
A peptide bond is formed tRNA molecule brings to along and reads the transcript, and
between the amino acids, the ribosome the amino a corresponding amino acid is
aligned next to each other. acid dictated by the next brought to the ribosome until the
codon. protein is completed.

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