University:
Sam Houston State University
Course:
BIOL 2413 | General Zoology
Academic year:

2022
Views:

157

Pages:

15
Author:

Clint W.

Now the message can be translated!! • A single strand of mRNA was just transcribed from DNA within the nucleus and now the code will be translated to make the specific protein within a ribosome in the cytoplasm!! • DNA strand • mRNA strand TACATTTAGCGG AUGUAAAUCGCC What is the structure of the mRNA code? • Three mRNA nucleotides form a triplet code called a “codon.” Each codon sequence will then code for a tRNA with an anticodon with opposite nitrogen bases . tRNA • Notice UGA anticodon at bottom of the tRNA • Notice Amino Acid at the top of the tRNA Genetic code • There are 64 combinations using the four mRNA nucleotides AUGC to code for 20 amino acids. Step 2 of Protein Synthesis • mRNA is used to pair up with tRNA to code for amino acids that form a chain to make a specific protein in a process called “translation.” What is “translation”? • A ribosome binds mRNA to tRNA, which is attached to specific amino acids as anticodons. Each anticodon of tRNA attaches to a codon on mRNA. An amino acid is attached to the top of a tRNA. The amino acids bond together, forming a polypeptide chain that make a specific protein. Where does translation take place? • In ribosomes in the cell’s cytoplasm tRNA anticodon (UAC) binds mRNA at the START codon (AUG) to begin the translation message Each tRNA caries a specific amino acid. The amino acids bind together to make a polypeptide chain to make specific proteins. • At the end (stop codon), a release enzyme binds to a stop codon in the sequence. This stops translation, releasing the completed chain of protein. Ct 1n Complete the following code!! • • • • • DNA DNA mRNA tRNA A.A AT _ CGG _ _ _ TGG TAC _ _ _ CGT ACC ____________ _ _C G _ _ _ _ _ _ _ _ ____ ____ ____ ____=Protein – (Use the table to find the correct amino acid) Complete the following code!! • • • • • DNA DNA mRNA tRNA A.A ATG CGG GCA TGG TAC GCC CGT ACC AUG CGG GCA UGG UAC GCC CGU ACC TRY ALA ARG THR = Protein – (Use the table to find the correct amino acid) How is this new animal protein used? • It may be used for: • Structure muscle, bone, hair • Cell membranes • Chemicals special enzymes Big Picture in Action