1. DNA & Protein Synthesis SC.912.L.16.3

2. When a cell replicates its DNA, what is the first thing that happens? A. The original DNA strand opens at several places along its length. B. One end of the DNA strand opens and the two sides pull apart. C. The DNA strand flattens out so a new double strand can form on top. D. Small segments are removed from the original DNA so they can be copied. A. The original DNA strand opens at several places along its length.

3. One side of a DNA strand is being replicated to make a new, complete strand of DNA. The original strand contains the following base sequence: A-T-T-C-G-C. What sequence of bases will be in the strand built from this sequence? A. A-T-T-C-G-C B. T-A-A-G-C-G C. C-G-G-A-T-A D. U-A-A-C-G-C B. T-A-A-G-C-G

4. At what point during the cell cycle is it most likely that a mutation involving a single incorrect base would occur? A. during prophase of mitosis B. during metaphase of meiosis C. during anaphase of meiosis D. during the S phase of interphase D. during the S phase of interphase

5. Not all mistakes in copying DNA result in changes to the proteins that are made from it. For instance, if a DNA sequence that should result in an mRNA codon that reads C-C-C is miscopied so that the codon produced reads C-C- G, no change will occur. Why is this? A. As long as the new codon stands for the same amino acid as the original codon, there will be no difference in the resulting protein. B. Guanine can be substituted for cytosine in a DNA strand without changing the meaning of the resulting strand of DNA. C. A large section of the DNA would have to be deleted or miscopied before there would be any functional change to the protein produced. D. Special enzymes check the sequence of amino acids in a completed protein and replace any amino acids that are in the wrong place. A. As long as the new codon stands for the same amino acid as the original codon, there will be no difference in the resulting protein.

6. Which answer explains why changes like pierced ears or scars in a mother's body are not passed on to her children? A. Piercing her ears or scars only altered the DNA at the site, not in any of the other cells in her body, so she could not pass them on. B. Only changes to the DNA in her egg cells would be passed on to her children, not changes to the rest of her body. C. Once the mother's scars or ears had healed, the DNA in those cells was repaired so there would be no changed DNA to pass on. D. The chance of the mutated DNA migrating all the way to her egg cells and getting passed to her children is very low. B. Only changes to the DNA in her egg cells would be passed on to her children, not changes to the rest of her body.

7. A strand of mRNA has made it to a ribosome in the cytoplasm and the ribosome has attached to the correct end of it. What is the next thing that will happen? A. The ribosome will fold the mRNA strand so it becomes a completed protein strand. B. The complementary bases will pair up with the mRNA to make a new DNA strand. C. Amino acids will begin to attach to the correct codons on the mRNA strand. D. The correct anticodon on a tRNA molecule will match up with the first mRNA codon. D. The correct anticodon on a tRNA molecule will match up with the first mRNA codon.

8. If the genetic code is a code for proteins, how can organisms have parts made of other types of biological molecules, such as the carbohydrates that make up the cell walls of plants? A. Other molecules such as mRNA hold the code for creating non-protein molecules within an organism. B. Carbohydrates are created during photosynthesis and do not require genetic information or proteins. C. Enzymes are made of protein and can be used as tools to build other types of molecules. D. Organisms must take in all of the non-protein molecules they require from their environment. C. Enzymes are made of protein and can be used as tools to build other types of molecules.

9. Which of the following would most likely cause a mutation that could be passed on to a person's children? A. being exposed to high levels of radiation in a nuclear power plant B. spending every weekend working outside in the sun C. eating a diet high in fiber, whole grains, and fruits and vegetables D. drinking large quantities of caffeinated beverages while pregnant A. being exposed to high levels of radiation in a nuclear power plant

10. Genes for medically important proteins can be cloned and inserted into bacteria, as shown in the diagram below. Why can bacteria recognize a human gene and then produce a human protein?

11. Why can bacteria recognize a human gene and then produce a human protein? A. DNA replication in bacteria and humans is the same. B. Bacterial cells contain the same organelles as human cells. C. The basic components of DNA are the same in humans and bacteria. D. Bacterial cells and human cells contain the same kind of chromosomes. C. The basic components of DNA are the same in humans and bacteria.

12. During DNA replication, a DNA strand that has the bases CTAGGT produces a complimentary (cDNA) strand with the bases a.GATCCA b.TCGAAC c.AGCTTC d.GAUCCA a. GATCCA

13. OUT OF 10 QUESTIONS 1/10 = 10% 2/10 = 20% 3/10 = 30% 4/10 = 40% 5/10 = 50% 5/10 = 50% 6/10 = 60% 6/10 = 60% 7/10 = 70% 7/10 = 70% 8/10 = 80% 9/10 = 90% 10/10 = 100%