Exam 3 Practice Questions - Cell Biology PDF

### **Chapter 11: Cell Communication - Practice Questions** #### **Concept 11.1: Introduction to Cell Signaling** 1. **What are two general reasons that cells use signaling mechanisms?** 2. **How old is the process of cell signaling in evolutionary terms?** 3. **In bacteria, cell signaling occur...

### **Chapter 11: Cell Communication - Practice Questions** #### **Concept 11.1: Introduction to Cell Signaling** 1. **What are two general reasons that cells use signaling mechanisms?** 2. **How old is the process of cell signaling in evolutionary terms?** 3. **In bacteria, cell signaling occurs through a process called quorum sensing. Describe this process and its significance.** 4. **How does quorum sensing differ between bacteria and yeast cells in terms of signaling?** 5. **The ability of a cell to respond to a signal molecule depends on the presence of a specific ________.** a) Receptor b) Signal molecule c) Second messenger d) Response enzyme 6. **What are the three stages of cell signaling as outlined in Figure 11.6? Briefly describe each stage.** --- #### **Concept 11.2: Reception** 7. **Describe the relationship between a receptor protein and its ligand.** 8. **Where are most receptor proteins typically located in a cell?** 9. **Compare and contrast the structure and function of the three major types of cell-surface transmembrane receptors as shown in Figure 11.8.** 10. **Describe the role of intracellular receptors and give an example of a signaling molecule (e.g., steroids) that binds to these receptors.** 11. **What types of ligands typically bind to intracellular receptors?** a) Hydrophobic ligands b) Hydrophilic ligands c) Peptide hormones d) Both a and c --- #### **Concept 11.3: Transduction** 12. **Explain the signal transduction pathway for signaling molecules that bind to protein kinases (Figure 11.10).** 13. **Using the terms phosphorylation, cascade, and dephosphorylation, explain how a signal transduction pathway can elicit a cellular response.** 14. **Describe the signal transduction pathway for signaling molecules that bind to a G-protein coupled receptor (GPCR) as illustrated in Figure 11.12.** 15. **What are second messengers, and why are they advantageous in signal transduction? Use cAMP as an example in your answer.** --- #### **Concept 11.4: Response** 16. **Describe two examples of cellular responses to signaling molecules as shown in Figures 11.15 and 11.16.** 17. **Why is signal amplification advantageous in glycogen breakdown, as shown in Figure 11.16?** 18. **Explain how two cells can respond differently to the same signaling molecule.** 19. **What is the role of scaffolding proteins in signal transduction? Provide an example of how they function.** 20. **Why is it important for a cell to terminate a signal once it has been processed?** --- #### **Concept 11.5: Apoptosis** 21. **What is apoptosis, and why is it important for the development and maintenance of animals? Provide an example from Figure 11.21.** --- Great! Here are some practice questions based on **Concept 12.1 to 12.3**. Again, I’ve included a variety of formats including multiple choice, short answer, and explanation-based questions. --- ### **Chapter 12: Cell Division - Practice Questions** #### **Concept 12.1: Introduction to Cell Division** 1. **What is the purpose of cell division in:** a) Unicellular organisms? b) Multicellular organisms? 2. **Using the following terms, explain how genetic material is organized in a eukaryotic cell:** - Genome - Chromosomes - Genes - Chromatin - Chromosome condensation - Sister chromatids - Centromere - Mitosis - Cytokinesis 3. **Define the following terms:** a) Gametes b) Somatic cells 4. **What is the difference between homologs and sister chromatids?** --- #### **Concept 12.2: The Cell Cycle and Mitosis** 5. **Explain the difference between interphase and M phase during cell division.** 6. **Describe the events that occur during each sub-phase of interphase:** a) G1 phase b) S phase c) G2 phase 7. **Review Figure 12.7 and describe the phases of mitosis.** a) In which phase are chromosomes relaxed and in which phase are they condensed?  b) Explain the structure and function of the mitotic spindle and kinetochore. c) How does the metaphase plate form during mitosis? d) At what point during mitosis does cytokinesis begin? 8. **Explain the process of cytokinesis in animal cells.** a) What is the cleavage furrow, and which part of the cytoskeleton is involved in its formation? 9. **Describe cytokinesis in plant cells.** a) What is the cell plate, and which membrane-bound organelles and part of the cytoskeleton are involved in its formation? --- #### **Concept 12.3: Cell Cycle Control and Cancer** 10. **What is the role of cell-cycle checkpoints in regulating cell division?** a) Explain how malfunction at a checkpoint might lead to cancer. 11. **What factors determine whether a cell enters the G0 phase of the cell cycle?** a) Why might a cell not proceed to the S phase and remain in G0? --- ### **Bonus: Application of Concepts** 12. **If a cell does not properly pass the G1 checkpoint, what are some possible outcomes for the cell?** 13. **Consider a situation where a mutation occurs that prevents the cleavage furrow from forming during cytokinesis in an animal cell. What would likely happen to the cell?** 14. **Explain the importance of chromosome condensation during mitosis. Why does it need to occur for the proper separation of genetic material?** 15. **What is the significance of the metaphase plate during mitosis, and how is it essential for accurate chromosome segregation?** --- Great, you're covering a lot of important concepts in genetics! Below are some practice questions based on **Concepts 13.1 to 13.4**, in various formats: --- ### **Chapter 13: Meiosis and Sexual Reproduction - Practice Questions** #### **Concept 13.1: Basic Genetic Concepts** 1. **Define the following terms:** a) Inheritance b) Heredity c) Variation d) Genetics 2. **What is the difference between:** a) Genes and gametes b) Somatic cells and clones c) Locus and genome 3. **How do asexual reproduction and sexual reproduction differ in terms of genetic variation and the mechanisms involved?** --- #### **Concept 13.2: Life Cycle, Meiosis, and Chromosome Number** 4. **Match the terms with their definitions:** a) Life cycle b) Karyotype c) Homologous chromosomes d) Sex chromosomes e) Autosomes f) Diploid (2n) g) Haploid (n) h) Fertilization i) Zygote j) Meiosis 5. **Review Figures 13.6 and 13.7.** a) Why do fertilization and meiosis alternate in sexual life cycles? b) What impact does fertilization have on chromosome number? c) How does meiosis impact chromosome number? 6. **Explain the relationship between fertilization and meiosis. How does ploidy change during the life cycle of an eukaryotic organism?** 7. **Can a haploid cell undergo:** a) Mitosis?  b) Meiosis? Explain your answers. --- #### **Concept 13.3: Meiosis and Genetic Variation** 8. **Review Figure 13.8. Describe the events during each sub-phase of meiosis I (Prophase I, Metaphase I, Anaphase I, Telophase I).** 9. **What happens to the nuclear envelope during each sub-phase of meiosis I and meiosis II?** 10. **What is the importance of cytokinesis following meiosis I and meiosis II?** 11. **Explain why synapsis, which is required for crossing over, can only occur during prophase I of meiosis. Why doesn’t crossing over occur in mitosis or meiosis II?** 12. **Which phases of meiosis are responsible for reducing the chromosome number from diploid to haploid?** 13. **Explain the relationship between chromosomes and sister chromatids. How do both structures represent a single chromosome?** 14. **Draw and label unreplicated vs. replicated chromosomes, showing sister chromatids.** 15. **Compare and contrast mitosis and meiosis based on the following:** a) Number of divisions b) Genetic variation in offspring c) Role in the organism's life cycle d) Chromosome number change --- #### **Concept 13.4: Genetic Variation and Reproduction** 16. **List three processes associated with sexual reproduction that produce genetic variation in offspring.** 17. **If the environment is stable and not changing, would it be better for a well-adapted organism to reproduce asexually or sexually? Justify your answer.** --- ### **Bonus: Application Questions** 18. **Imagine a scenario where a cell undergoes meiosis but fails to separate homologous chromosomes during anaphase I. What would be the genetic outcome of this error?** 19. **If a cell undergoes meiosis but fails to complete cytokinesis after meiosis II, what would be the result for the daughter cells?** 20. **In a particular organism, crossing over occurs during meiosis I. What is the impact of crossing over on the genetic diversity of the resulting gametes?** --- Great! Here are practice questions based on **Concepts 14.1 to 14.4**, focusing on Mendelian genetics, inheritance patterns, and genetic counseling: --- ### **Chapter 14: Mendelian Genetics and Human Inheritance - Practice Questions** #### **Concept 14.1: Mendel's Peas and His Experimental Approach** 1. **Why was the garden pea an ideal organism for Mendel’s studies? What characteristics made it a good model organism?** 2. **What experimental approach did Mendel use, and why was it successful?** a) Define the following terms in relation to Mendel’s experiments: - Character - Trait - True-breeding - Hybridization - P generation - F1 generation - F2 generation 3. **Compare and contrast the "blending" model of inheritance with the "particulate" model.** a) How did Mendel’s work challenge the blending inheritance hypothesis? b) What evidence did Mendel gather that rejected the idea of inheritance of acquired characters? 4. **How many pea characters did Mendel study?** a) What is the haploid number for pea plants? 5. **Review Figure 14.5 and explain Mendel’s model of inheritance.**  a) What is the law of segregation? b) How does the law of segregation relate to the ploidy of gametes and the movement of chromosomes during meiosis? 6. **Define the following genetic terms:** - Allele - Dominant allele - Recessive allele - Punnett square - Homozygote - Homozygous dominant - Homozygous recessive - Heterozygote - Heterozygous - Phenotype - Genotype 7. **What genotypic and phenotypic ratios did Mendel observe in the F1 and F2 generations of a monohybrid cross?** a) What was the genotypic ratio? b) What was the phenotypic ratio? 8. **Explain the test cross.** a) What is the purpose of a test cross? b) Are there quicker ways to determine an organism's genotype? 9. **Explain the terms:** - Monohybrid - Monohybrid cross - Dihybrid - Dihybrid cross 10. **What phenotypic ratios did Mendel observe in the F1 and F2 generations of a dihybrid cross?** a) Use a Punnett square to predict the outcome of a monohybrid cross. b) Use a Punnett square to predict the outcomes of a dihybrid cross. c) How did the result of the dihybrid cross involving seed shape and color support Mendel’s law of independent assortment? 11. **What is Mendel’s law of independent assortment?** a) Were Mendel’s characters located on the same chromosome or different chromosomes? --- #### **Concept 15.1: Chromosomal Basis of Inheritance** 12. **Demonstrate Mendel’s laws of segregation and independent assortment by placing alleles on chromosomes.** a) Describe how the chromosomes behave during the phases of meiosis to explain these laws. 13. **Identify the steps in meiosis that account for the law of segregation and the law of independent assortment.** 14. **Describe the chromosomal theory of inheritance.** a) How does the chromosomal theory of inheritance through meiosis support Mendel’s principles of segregation and independent assortment? --- #### **Concept 14.2: Probability in Genetics** 15. **What is the multiplication rule of probability?** a) Provide an example of how this rule is applied in genetics. 16. **What is the addition rule of probability?** a) Provide an example of how this rule is applied in genetics. --- #### **Concept 14.4: Human Inheritance and Genetic Counseling** 17. **Why are humans not ideal subjects for genetic studies?** 18. **What is a pedigree, and how can pedigree analysis be useful in understanding inheritance patterns?** a) Review Figure 14.15 and explain how a pedigree is used to trace inheritance of traits. 19. **What are examples of human traits or disorders that result from inheriting:** a) Recessive alleles? b) Dominant alleles? 20. **What is a carrier?** a) How does a carrier differ from a person with a dominant or recessive disorder? 21. **Be familiar with the following terms in genetic counseling:** - Carrier testing - Fetal testing  - Amniocentesis - Chorionic villus sampling (CVS) - Newborn screening --- ### **Bonus: Application Questions** 22. **In a monohybrid cross between two heterozygous pea plants (Aa), what are the expected phenotypic and genotypic ratios in the F2 generation?** 23. **Explain why the results of a dihybrid cross (e.g., between plants with different seed colors and shapes) support the concept of independent assortment. What would happen if the genes for seed color and shape were linked on the same chromosome?** 24. **A woman has a genetic disorder caused by a recessive allele. If her partner is a carrier, what is the probability that their child will inherit the disorder? Use a Punnett square to explain your answer.** --- Great, you're covering a lot of important topics! Below are practice questions based on **Concepts 14.3 to 15.5**, focusing on advanced genetic concepts, sex determination, chromosomal abnormalities, and mitochondrial inheritance. --- ### **Chapter 14: Complex Inheritance Patterns and Human Genetics - Practice Questions** #### **Concept 14.3: Complex Inheritance Patterns** 1. **What is the difference between incomplete dominance and codominance?** a) Use the example of snapdragon flower color to explain incomplete dominance. b) Use the MN blood group to explain codominance. 2. **Explain how the ABO blood group in humans demonstrates the concept of multiple alleles.** a) What are the three alleles involved in the ABO blood group system? b) How do they interact to produce different blood types? 3. **What is pleiotropy?** a) Provide some examples of pleiotropic traits in humans or animals. 4. **Explain epistasis using the example of Labrador retriever coat color inheritance.**  a) How does the presence of one allele affect the expression of another gene in this example? 5. **Explain polygenic inheritance using human skin color.** a) What is meant by "quantitative characters" in relation to polygenic inheritance? b) Give examples of other traits that exhibit polygenic inheritance. 6. **What is meant by "nature and nurture" in genetics?** a) Provide examples where both genetic and environmental factors play a role in determining a trait. b) What does "multifactorial" mean in genetics? --- #### **Concept 14.4: Sickle-Cell Disease and Evolution** 7. **How is the sickle-cell allele both recessive, incompletely dominant, and codominant?** a) Explain why heterozygotes for the sickle-cell allele have a different phenotype from homozygotes. 8. **Why is the sickle-cell allele favored under certain conditions, and why hasn't it been selected against by evolutionary processes?** a) How does the sickle-cell allele provide a selective advantage in areas where malaria is common? --- #### **Concept 15.1: Sex Chromosomes and Drosophila Genetics** 9. **Why did Thomas Hunt Morgan choose Drosophila melanogaster (fruit flies) to study genetics?** a) List some advantages of using fruit flies in genetic research. b) What sex chromosomes do male and female fruit flies possess? 10. **Explain the following terms:** - Wild-type phenotype - Mutant phenotype 11. **What two important ideas came from Thomas Hunt Morgan’s research on fruit flies?** --- #### **Concept 15.2: Sex Determination Systems** 12. **Review Figures 15.5 and 15.6.**  a) Draw the symbols for male and female in mammals. b) How is sex determined in mammals? c) Compare the X and Y chromosomes. How do they act as a homologous pair in meiosis? 13. **Explain the following terms:** - SRY gene - Sex-linked gene - X-linked gene - Y-linked gene - WNT4 gene 14. **Are most Y-linked and X-linked genes related to sex determination?** 15. **Provide examples of human X-linked genes.** a) What is the notation used for X-linked alleles (e.g., X^A, X^a)? 16. **Explain the following terms:** - X-inactivation - Barr body - Mosaic --- #### **Concept 15.3: Linkage and Gene Mapping (Skip for now)** --- #### **Concept 15.4: Chromosomal Alterations and Nondisjunction** 17. **Review Figure 15.13 and explain nondisjunction in meiosis.** a) What is aneuploidy? b) Define monosomic and trisomic. c) Provide examples of conditions caused by nondisjunction (e.g., Down syndrome). 18. **Briefly explain nondisjunction in mitosis.** a) How is it different from nondisjunction in meiosis? 19. **Review the four types of chromosomal structural alterations in Figure 15.14.** a) What causes these changes in chromosomal structure? b) Provide examples of disorders caused by these structural changes. 20. **What are some examples of human aneuploidies?** a) Trisomy 21 (Down syndrome) b) XXY (Klinefelter syndrome)  c) XYY syndrome d) XXX syndrome e) X0 (Turner syndrome) --- #### **Concept 15.5: Mitochondrial Inheritance and Maternal Inheritance** 21. **How can genes in the mitochondrion and chloroplast affect organisms?** a) Explain how mitochondrial DNA is inherited. b) Provide an example of a mitochondrial disease. 22. **What does “3-parent babies” mean?** a) Explain the concept of mitochondrial replacement therapy and its ethical considerations. --- ### **Bonus: Application Questions** 23. **A woman with blood type A (genotype I^Ai) and a man with blood type B (genotype I^Bi) have a child. What are the possible blood types and genotypes of their offspring? Use a Punnett square to predict the outcomes.** 24. **A person has a skin color determined by polygenic inheritance. If both parents have medium-dark skin, what is the likelihood that their child will have light skin?** 25. **A woman has a disorder caused by an X-linked recessive allele, and her husband is unaffected. What is the probability that their son will inherit the disorder?** 26. **A child inherits two X chromosomes (XX) from their mother and father. What genetic condition could be associated with this inheritance pattern if one of the X chromosomes is inactivated?** --- These questions cover a wide range of topics, from complex inheritance patterns like codominance and epistasis to more advanced topics like sex determination and chromosomal disorders. Let me know if you need further explanations or more practice questions! EXAM 3 SAMPLE Qs FROM GONSAR During____ of mitosis, chromosomes line up at the equator of the cell. a. Prophase b. Telophase c. Anaphase d. Metaphase e. Prometaphase How many different gametes could be produced through independent assortment by an individual with the genotype AaBbCCDdEE? What are the molecules that make up chromosomes? What are the 3 types of cell membrane receptors? Vitamin D is a relatively small lipid-soluble molecule that can behave as a hormone. Its receptor, therefore most likely is a. Located inside the cell b. Is a protein kinase receptor c. Is an ion channel receptor d. Does not exist, since the molecule can diffuse across the cell membrane Which designates the correct order of Mendel's three-generation crosses? a) F1, F2, P b) F2, F1, P c) P, F1, F2 d) F1, P, F2 A child is born with phenylketonuria, or PKU, a recessive disorder, but his parents are unaffected. What are the parents' possible genotypes? What response is stimulated by cell signaling that form biofilms? How does a nucleus in G2 differ from a nucleus in G1? What 2 specific processes occur during meiosis that contribute to genetic variation in sexual organisms. Cytokinesis occurs in plants by ______________ formation. A chicken has 78 chromosomes in its somatic cells (1pt). a. How many chromosomes are in each of the chicken’s gametes? _____ b. How many chromosomes will be in each somatic cell of the chicken’s offspring?_____ A rabbit smells a fox as it passes by and quickly bounds to safety. Which sequency represented the correct order of steps in the signal transduction pathway that is involved. a. Receptor binds signal--> conformational change occurs in signal---signal travels to target cell—signal is transduced within cell—effects from signal transduction occur. b. Signal travels to target cell-->receptor binds signal-->conformation change occurs in receptor --->signal transduced within cell-->effects from signal transduction occurs. c. Cell responds to signal-->Signal travels to target cell-->Signal is traduced within cell-->effects from signal transduction occurs. Humans have _________pair of autosomes The figure below shows metaphase I of meiosis. A) How is the arrangement of chromosomes here different from the metaphase of mitosis? B) Label the differently shaded chromosomes.