8 5 Translation KEY CONCEPT Translation converts an

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8. 5 Translation KEY CONCEPT Translation converts an m. RNA message into a polypeptide,

8. 5 Translation KEY CONCEPT Translation converts an m. RNA message into a polypeptide, or protein.

8. 5 DNA Translation and Translation • Gene: section of DNA that creates a

8. 5 DNA Translation and Translation • Gene: section of DNA that creates a specific protein – Approx 25, 000 human genes • Proteins are used to build cells and tissue • Protein synthesis involves two processes: 1) Transcription 2) Translation

8. 5 Translation • Transcription takes place in the nucleus – 1) DNA double

8. 5 Translation • Transcription takes place in the nucleus – 1) DNA double helix is broken apart – 2) m. RNA nucleotides match up – 3) Finished m. RNA detaches, and moves to a ribosome

8. 5 Translation Amino acids are coded by m. RNA base sequences. • Translation

8. 5 Translation Amino acids are coded by m. RNA base sequences. • Translation converts m. RNA messages into polypeptides. • A codon is a sequence of three nucleotides that codes for an amino acid. codon for methionine (Met) codon for leucine (Leu)

8. 5 Translation • The genetic code matches each codon to its amino acid

8. 5 Translation • The genetic code matches each codon to its amino acid or function. • Each reading frame gives a codon The genetic code matches each RNA codon with its amino acid or function. – three stop codons – one start codon, codes for methionine

8. 5 Translation • A change in the order in which codons are read

8. 5 Translation • A change in the order in which codons are read changes the resulting protein. • Regardless of the organism, codons code for the same amino acid.

8. 5 Translation Amino acids are linked to become a protein. • An anticodon

8. 5 Translation Amino acids are linked to become a protein. • An anticodon is a set of three nucleotides that is complementary to an m. RNA codon. • An anticodon is carried by a t. RNA.

8. 5 Translation • Ribosomes consist of two subunits. – The large subunit has

8. 5 Translation • Ribosomes consist of two subunits. – The large subunit has three binding sites for t. RNA. – The small subunit binds to m. RNA.

8. 5 Translation • For translation to begin, t. RNA binds to a start

8. 5 Translation • For translation to begin, t. RNA binds to a start codon and signals the ribosome to assemble. 1 – A complementary t. RNA molecule binds to the exposed codon, bringing its amino acid close to the first amino acid.

8. 5 Translation 2 – The ribosome helps form a peptide bond between the

8. 5 Translation 2 – The ribosome helps form a peptide bond between the amino acids. – The ribosome pulls the m. RNA strand the length of one codon.

8. 5 Translation 3 – The now empty t. RNA molecule exits the ribosome.

8. 5 Translation 3 – The now empty t. RNA molecule exits the ribosome. – A complementary t. RNA molecule binds to the next exposed codon. – Once the stop codon is reached, the ribosome releases the protein and disassembles.

8. 5 Translation • Name the parts! 1. Amino acid 2. Peptide bond 3.

8. 5 Translation • Name the parts! 1. Amino acid 2. Peptide bond 3. Ribosome- large subunit 4. t. RNA 8. Anticodon 7. m. RNA 6. Ribosome- small subunit 5. Reading frame/binding site (start codon)

8. 5 Translation

8. 5 Translation

8. 5 Translation Practice Problem DNA m. RNA codon t. RNA anticodon Amino Acid

8. 5 Translation Practice Problem DNA m. RNA codon t. RNA anticodon Amino Acid

Practice Problem 8. 5 Translation DNA m. RNA codon t. RNA anticodon Amino Acid

Practice Problem 8. 5 Translation DNA m. RNA codon t. RNA anticodon Amino Acid