1. Which one of the following is a different between sexual and asexual reproduction? a. Sexual reproduction includes the development of unfertilized eggs b. Sexual reproduction produces more offspring c. Regeneration is exclusive to sexual reproduction d. Sexual reproduction is more likely to increase genetic variation than is asexual reproduction e. Asexual reproduction always increases the number of sets of chromosomes in the offspring; sexual reproduction decreases the number of sets of chromosomes in the offspring The following questions refer to the essential steps in meiosis described below a. Formation of four new nuclei, each with half the chromosomes present in the parental nucleus b. Alignment of tetrads at the metaphase plate c. Separation of sister chromatids d. Separation of the homologous chromosomes; no uncoupling of the centromere e. Synapsis; chromosomes moving to the middle of the cell in pairs 2. From the descriptions above, which of the following is the order that most logically illustrates a sequence of meiosis a. 1, 2, 3, 4, 5 b. 5, 4, 2, 1, 3 c. 5, 3, 2, 4, 1 d. 4, 5, 2, 1, 3 e. 5, 2, 4, 3, 1 3. Which of the steps take place in both mitosis and meiosis? a. 2 b. 3 c. 5 d. 2 and 3 e. 2, 3, and 5 4. With the exception of identical twins, siblings who have the same two biological parents are likely to look similar, but not identical, to each other because they have a. Only a 50% chance of being the same sex b. Some gene variants in common c. Gene variants not found in the other d. No gene variants in common e. Some gene variants in common and some variants not found in the other 5. Prior to mitosis, each chromosome of a eukaryotic cell consists of a pair of identical structures called a. Nucleoli b. Sister chromatids c. DNA transcripts d. Chromatin e. Sister chromatids 6. Eukaryotic cells spend most of their cell cycle in which phase? a. Interphase b. Anaphase c. Metaphase d. Telophase e. Prophase 7. For a species with a diploid number of 10 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes? a. 5 b. 25 c. 32 d. 100 e. About 10,000 8. If the S phase was eliminated from the cell cycle, the daughter cells would a. Be genetically identical to the parental cell b. Synthesize the missing genetic material on their own c. Be genetically identical d. Have half the genetic material found in the parental cell e. None of the choices are correct 9. During which phase of mitosis do the chromosomes line up on a plane located equidistant from the two spindle poles? a. Telophase b. Prophase c. Interphase d. Metaphase e. Anaphase 10. If the cell whose nuclear material is show in Figure 12.2 continues toward completion of mitosis, which of the following events would next occur? Figure 12.2 a. b. c. d. e. Cell membrane synthesis Spindle fiber formation Nuclear envelope breakdown Formation of telophase nuclei Synthesis of chromatids 11. Which of the following is likely to account for the difference between plant and animal cell cytokinesis? a. Animal cells lack chloroplasts b. Plant cell division must maintain the integrity of the cell wall c. Plant and animal cells do not have a common ancestor d. Plant cells have two sets of chromosomes; animal cells only have one set of chromosomes e. Plants cells lack the microfilaments required for forming a cleavage furrow 12. Which of the following is a consequence of a reproduction system that is based on the union of haploid gametes? a. Offspring that have enhanced genetic diversity and a diploid chromosome complement that is twice the size of their parents’ b. The prevention of sexual reproduction c. Offspring with enhanced homozygosity d. Offspring that have enhanced genetic diversity and a diploid chromosome complement that is the same as their parents’ e. A reduction in the number of offspring with undesirable traits 13. Which of the following is a different between mitosis and meiosis? a. In meiosis four daughter cells are produced, whereas in mitosis two daughter cells are produced b. In mitosis cytokinesis occurs once, whereas in meiosis cytokinesis occurs twice c. Cells produced by mitosis are diploid; cells produced by meiosis are haploid d. All of the choices are correct 14. Independent orientation (assortment of chromosome) results in an increase in the number of a. Homologous chromosomes b. Sex chromosomes c. Gametes d. Points of crossing over e. Possible combination of characteristics 15. Karyotyping a. Reveals the results of independent orientation of chromosomes during meiosis I b. Reveals the presence of cancerous genes c. Can reveal alterations in chromosome number d. Shows chromosomes as they appear in metaphase of meiosis II e. Examines points of crossing over 16. Nondisjunction occurs when a. A portion of a chromosome breaks off and is lost b. An entire pair of chromosomes is lost during meiosis I c. Members of a chromosome pair fail to separate d. Chromosomes replicate too many times e. Two chromosomes fuse into one 17. If a chromosome fragment breaks off and then reattaches to the original chromosome but in the reverse direction, the resulting chromosomal abnormality is called a(n) a. Inversion b. Reciprocal translocation c. Nondisjunction d. Translocation e. Deletion 18. Examine the following sentence. “Where is the cat?” Which one of the following variations of this sentence is most like a chromosomal deletion? a. Where is the cat the the cat? b. Where is cat? c. Where is is is is the cat? d. Where is the the cat? e. Where the is cat? 19. Cancer is not usually inherited because a. People with cancer usually die before reproducing b. The causes of cancer are not usually genetic c. The chromosomal changes in cancer are usually confined to somatic cells d. The cancerous cells usually interfere with the ability to produce gametes e. Cancer typically causes disruptions in meiosis 20. The creation of offspring carrying genetic information by just a single parent is called a. Regeneration b. Sexual reproduction c. Asexual reproduction d. A life cycle e. None of the choices are correct Use the following information to answer the questions below. The lettered circle in Figure 12.1 shows a diploid nucleus with four chromosomes. There are two pairs of homologous chromosomes, one long and the other short. One haploid set is symbolized as black and the other haploid set is gray. The chromosomes in the unlettered circle have not yet replicated. Choose the correct chromosomal conditions for the following stages. Figure 12.1 21. One daughter nucleus at telophase of mitosis 22. One daughter nucleus at telophase of meiosis II 23. At prophase of mitosis 24. When animal cells are grown in a Petri dish, they typically stop dividing once they have formed a single, unbroken layer on the bottom of the dish. This arrest of division is an example of a. Cancer b. Cell division repression c. Density-dependent inhibition d. Cell constraint e. Growth factor desensitization 25. Which one of the following statements is NOT true? a. Gametes are haploid cells b. Gametes are made by mitosis c. Somatic cells are diploid d. A typical body cell is called a somatic cell e. A zygote is a fertilized egg Use the data in Table 12.1 to answer the following questions The data were obtained from a study of the length of time spent in each phase of the cell cycle by cells of three eukaryotic organisms designated beta, delta, and gamma. Cell Type Beta Delta Gamma Table 12.1: Minutes Spent in Cell Cycle Phases G1 S G2 18 24 12 100 0 0 18 48 14 M 16 0 20 26. Of the following, the best conclusion concerning the different between the S phases for beta and gamma is that a. Gamma contains more DNA than beta b. Beta and gamma contain the same amount of DNA c. Beta contains more RNA than gamma d. Gamma contains 48 times more DNA and RNA than beta e. Beta is a plant cell and gamma is an animal cell 27. How is the S phase of the cell cycle measured a. Counting the number of cells produced per hour b. Determine the length of time during which DNA synthesis occurred in the cells c. Comparing the synthesis versus the breakdown of S protein d. Determining when the S chromosome is synthesized e. Stopping G1 and measuring the number of picograms of DNA per cell 28. A group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA per nucleus. Those cells would have ______ picograms at the end of the S phase and _________ picograms at the end of G2. a. 8; 8 b. 8; 16 c. 16; 8 d. 16; 16 e. 12; 16 29. For a species with a haploid number of 23 chromosomes, how many different combinations of maternal and paternal chromosomes are possible for the gametes? a. 23 b. 46 c. 460 d. 920 e. About 8 million 30. If the DNA content of a diploid cell in the G1 phase of the cell cycle is “x” then the DNA content of the SAME cell at metaphase of meiosis I would be a. 0.25x b. 0.5x c. x d. 2x e. 4x 31. If we continued to follow the cell lineage from the previous question, then the DNA content at metaphase of meiosis II would be a. 0.25x b. 0.5x c. x d. 2x e. 4x 32. a) Sketch comparing diagrams of a nondisjunction event in meiosis I versus a nondisjunction event in meiosis II b) Using your diagram from part a and your knowledge of biology, explain why a nondisjunction event in meiosis I is more harmful than a nondisjunction event in meiosis II.