Monster Lab
Simulating Protein Synthesis Your unique body characteristics ( traits ), such as hair color or blood type, are determined by the proteins your body produces. Proteins are the building blocks of life – in fact, about 45% of the human body is made of protein. These organic macromolecules perform a wide range of functions including body repair, regulation, and protection. Proteins are created by bonding groups of amino acids that are coded for by the nucleotide base sequences (A, T, G, C) in your DNA. DNA is trapped in the nucleus because it is too wide to escape through the small nuclear pores in the nuclear membrane. This is a big issue for the cell, since proteins are made outside the nucleus in the cytoplasm. For this reason, a process called transcription occurs. DNA passes on its nucleotide base sequences, or code, to a single-stranded molecule called mRNA (messenger). mRNA then carries the code out to the cytoplasm to the ribosomes , the site where proteins are made. When the mRNA reaches the ribosome, the code in the mRNA nucleotides are read in groups of three bases, or codons . Each codon signals another type of RNA, called tRNA (transfer), to carry a specific amino acid into the ribosome. As amino acids continue to bond to one another it forms a polypeptide chain that eventually results in a protein. This process is known as translation. In this investigation, you will simulate protein synthesis by transcribing the DNA and translating the mRNA of the imaginary CHNOPS monster. The CHNOPS monster’s cells contain only one chromosome that carries nine genes: A, B, C, D, E, F, G, H, & I each of which code for a specific trait. You will decode each gene to determine the phenotypic expression of the CHNOPS monster’s DNA, and then draw the monster based on your results. Procedure 1. Transcribe and record the mRNA from the DNA sequence in each gene data table. 2. Next, translation would occur resulting in the anticodon sequence that is complementary to the mRNA base sequence. tRNA transfers the amino acids to the ribosome. 3. Use Figure 1 to translate the mRNA and record amino acids sequences. 4. Use the sequence of amino acids and Figure 2 to record the inherited phenotype and trait. 5. Create your imaginary CHNOPS monster based on the results of the gene expression. 6. Complete the discussion questions on your answer sheet. 7. Figure 1 Figure 2 Amino Acid Sequence Trait Phenotype Gly – Arg – Cys Blue Skin Gly – Arg – Arg Green Skin Gly – Arg – Phe Yellow Skin Ile – Ile – Leu Black Hair Ile – Ile – Asn Orange Hair Phe – Lys 1 Antennae Phe – Val 2 Antenna Phe – Asn 3 Antenna Pro – Pro – Tyr 6 Eyes Pro – Tyr – Arg 4 Eyes Pro – Tyr – Glu 1 Eye Thr – Glu – Tyr Nice Thr – Gly – Tyr Mean Ser – Arg 2 Legs Ser – Asn 3 Legs Ser – Lys 4 Legs Gly – Arg – Lys – Pro Pink polka dots Glu – Arg – Lys – Pro Purple polka dots Gly – Lys – Asn Tail Gly – Lys – Ile No Tail Asn – Thr 2 Arms Asn – Pro 4 Arms
