Unit 6: Genetics & Molecular Genetics Assessment

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1 Unit 6: Genetics & Molecular Genetics Assessment 1. NA replication takes place in the nucleus of eukaryotic cells during interphase. An enzyme called NA helicase relaxes the helix in certain places and separates the two strands of NA into two single strands. What is the next step in NA replication? (SC.912.L.16.3) A. NA polymerase adds new complementary nucleotides.. Enzymes copy two new strands that match the two original strands. C. Enzymes break down the hydrogen bonds between base pairs.. NA polymerase proofreads each strand to make sure the sequence is correct. 2. The making of messenger RNA takes place during transcription. In this process, a segment of NA called a gene serves as a template to produce a complementary mrna molecule. Transcription is known to have a less effective proofreading stage than NA replication has. What effect does this have on mrna? (SC.912.L.16.3, SC.912.L.16.5) A. Errors in the base sequences will result in a damaged strand of NA.. The base sequences of mrna can be exactly the same as those on NA. C. It is likely that there will be more errors in base sequences of mrna than in the NA.. It is likely that there will be fewer errors in base sequences of mrna than in the NA.

2 3. Hemoglobin is the protein in red blood cells that allows these cells to carry oxygen. Sickle-cell anemia is a disease in which an abnormal form of hemoglobin is produced, causing the normally round shaped cells to be sickleshaped. Ultimately, this results in a reduction in red blood cells and in oxygen delivery. Scientists hope to treat sickle-cell anemia in the near future with gene therapy by inserting the correct NA code for making hemoglobin into the cells that make red blood cells. How will this treatment fix the problem? (SC.912.L.16.10) Normal-red blood cell Sickleshaped red blood cell A. The inserted NA will bind to and fix the abnormal hemoglobin molecules, allowing them to carry more oxygen.. The inserted NA will provide the instructions for the synthesis of normal hemoglobin, which the cells will then start to make, resulting in the production of normal red blood cells. C. The NA will shut off the cells producing abnormal hemoglobin, allowing other cells to develop.. The NA will function to take up any extra oxygen the abnormal hemoglobin was unable to carry. 4. Use the chart and your knowledge of biology to help you answer the following question. Which NA sequence will produce a mrna codon that codes for the amino acid valine? (SC.912.L.16.3, SC.912.L.16.5) A. T-G-G. G-A-T C. C-G-A. C-A-A

3 5. Our genetic code is written using the four bases found in NA. When this code is transcribed into mrna, three-base segments called codons are translated into amino acids, which are then assembled into the correct protein. Why is this code called the Universal Code? (SC.912.L.16.3, SC.912.L.16.9) A. Some amino acids are coded for by more than one codon.. Each codon codes for the same amino acid in nearly every organism on Earth. C. Changing the order of the bases in NA changes the bases in the resulting mrna, which may change the amino acid coded for by that codon.. The codons in the NA of most living things are mixed with noncoding sequences of bases. 6. Four different segments of a NA molecule are represented below. Segment 1 Segment 2 Segment 3 Segment 4 T-A-G-G-C G-G-T-G-A G-A-T-T-A C-A-A-T-C A-T-C-C-G C-C-A-C-T C-C-A-A-T G-T-T-A-G Although it is very rare, random errors called mutations may occur during the process of NA replication. Of the segments listed above, which contain errors? (SC.912.L.16.3, SC.912.L.18.1) A. Segment 1 & Segment 2. Segment 3 & Segment 4 C. Segment 2 only. Segment 3 only

4 7. The diagram below shows part of a NA molecule. Genetic material can be mutated by natural events, such as exposure to harmful ultraviolet radiation. When this occurs, nucleotide sequences can be inverted. What may happen if two of the base pairs on this segment of NA were inverted? (SC.912.L.16.3, SC.912.L.16.4) A. A different protein could be made.. Translation would stop at that point. C. The strand would not be replicated.. The rest of the NA strand would detach and unravel. 8. iological macromolecules are organized into four major categories. One type of macromolecule is made of monomers that contain a phosphate group bonded to a five-carbon sugar bonded to a nitrogen base, as shown in the diagram below. Which of the following is an example of this type of monomer? (SC.912.L.18.1) A. Sucrose. Guanine. C. Peroxide. Lard

5 The pedigree chart below is for a family, some of whom exhibit the recessive trait, woolly hair. Affected individuals are indicated by a darkened square or circle. ased on the pedigree chart, what is the genotype of person 5 in the generation? (SC.912.L.16.1) A. WW. Ww C. ww. WW or ww 10. Two parents are found to be carriers of a genetic disorder caused by a recessive allele (a). Offspring born with two recessive alleles die before becoming old enough to reproduce. Which Punnett square could you use to predict the likelihood of these parents having an offspring with the disorder? (SC.912.L.16.1) A.. C..

6 11. The table lists the possible phenotypes for flower color where allele R exhibits incomplete dominance over R. Genotype RR R R RR Phenotype Red White Pink Heterozygous flowers have pink phenotypes. What percent of offspring are expected to have a pink phenotype if the parent plants are pink (RR') and white (R'R')? (SC.912.L.16.1, SC.912.L.16.2) A. 25%. 50% C. 75%. 100% 12. A tall pea plant with purple flowers has the genotype TtRr This plant is crossed with another tall pea plant with white flowers, having the genotype Ttrr. What is the probability of getting dwarf plants with red flowers in the F1 progeny? (SC.912.L.16.1, SC.912.L.16.2) A. 1 out of 8. 1 out of 4 C. 3 out of 8. 1 out of Eye color is genetically determined. rown eyes are dominant to blue eyes. If a homozygous brown-eyed man marries a heterozygous brown-eyed woman, what is the probability that their child will have brown eyes? (SC.912.L.16.1) A. 25%. 50% C. 75%. 100%

7 14. Scientists genetically modified a variety of corn to protect it against pests like the corn borer. The corn borer is an insect caterpillar that feeds on the corn stalk, which weakens the stalk and makes it fall over. A new gene in the genetically modified corn causes the plant to produce a chemical that is toxic to the corn borer. Some people are concerned that the genetically modified corn could harm other insects such as the monarch butterfly caterpillar. The monarch caterpillar eats leaves of milkweed plants that might be coated with toxic corn pollen. However, not all researchers agree with the concerns regarding the monarch butterfly caterpillar. They state that it is unusual for large amounts of harmful corn pollen to be found on milkweed leaves. Also, only a small percentage of caterpillars feed on the milkweed plants near corn fields. (SC.912.L.16.10) What concern do scientists have about the monarch butterfly caterpillar consuming milkweed plants coated with modified corn pollen? A. The milkweed population would decline.. The caterpillars could spread the modified pollen. C. The food source of the monarch butterfly could be contaminated.. The caterpillars could pass the toxin to the milkweed plants. 15. Rice is a staple food source for much of the world s population. At present, there is a limited region in which rice can be grown successfully. If world climate change continues as scientists predict, the rice-growing region will become even more limited. Which of the following is an example in which biotechnology could be used to keep rice harvests from declining? (SC.912.L.16.10) A. Identifying new areas with soil fertile enough for rice production.. Seeding clouds with dry ice to produce more rainfall where it is needed. C. eveloping clean energy sources to reduce CO2 production worldwide.. Genetically engineering rice crops that can grow well in warmer climates.

8 16. Transgenic organisms are organisms into which scientists have transferred genes from another species. What is the main ethical argument against the use of transgenic organisms? Transgenic organisms may (SC.912.L.16.10) A. Cause unknown effects in an ecosystem.. Eliminate certain harmful diseases. C. Increase food production in many crops.. Prevent harmful mutations. 17. If a man with blood type A and a woman with blood type produce an offspring, what are the possible blood types that their child could have? lood Types lood Type Combination of Alleles A I A I A or I A i I I or I i A I A I O ased on this information, which of the following blood types are possible for their offspring to inherit? (SC.912.L.16.1, SC.912.L.16.2) A. A or O. A,, or O C. A,, A, or O. A only ii 18. Most sex-linked, recessive traits including hemophilia and color blindness appear in males more often than in females. This phenomenon is best explained by which statement? (SC.912.L.16.1, SC.912.L.16.2) A. Males have a dominant X chromosome with dominant genes.. Most of the genes on the X and Y chromosome of males are recessive. C. In males, the recessive sex-linked genes appear only on the Y chromosome.. The Y chromosome is not homologous to the X chromosome, so it lacks the genes needed to mask the recessive gene on the X chromosome.

9 19. Three cellular processes X, Y, and Z are shown in the diagram below. Which of the following answers names the process shown in Step Y and where it is occurring in the cell? (SC.912.L.16.3, SC.912.L.16.5) A. Translation; nucleus. Transcription; ribosome C. Translation; ribosome. Transcription; nucleus 20. uring the cell cycle, before a cell goes through mitosis, which of the following processes must be completed, and in which phase of the cycle? (SC.912.L.16.3, SC.912.L.16.17) A. Transcription; during M-phase. Replication; during S-phase C. Replication; during G1-phase.. Transcription; during G2-phase.

10 Answer Key Unit 6: Genetics & Molecular Genetics Assessment Question # enchmark(s) SC.912.L.16.3 SC.912.L.16.3, SC.912.L.16.5 SC.912.L SC.912.L.16.3, SC.912.L.16.5 SC.912.L.16.3, SC.912.L.16.9 SC.912.L.16.3, SC.912.L.18.1 SC.912.L.16.3, SC.912.L.16.4 SC.912.L.18.1 Answer 9 SC.912.L.16.1 C 10 SC.912.L.16.1 A C A 11 SC.912.L.16.1, SC.912.L SC.912.L.16.1, SC.912.L SC.912.L SC.912.L SC.912.L SC.912.L SC.912.L.16.1, SC.912.L SC.912.L.16.1, SC.912.L SC.912.L.16.3, SC.912.L SC.912.L.16.3, SC.912.L A C A C