Unit 6: The Cell Cycle and Cancer - Practice Quiz

1 Which phase of the cell cycle is mainly associated with cell growth and preparation for DNA replication?

2 During which phase of the cell cycle is DNA replicated?

3 What is the main result of the cell cycle in a typical somatic cell?

4 Which type of cell division produces gametes such as sperm and eggs?

5 How many daughter cells are produced by one round of mitosis?

6 What is a major difference between meiosis and mitosis?

7 What is the main function of a cell-cycle checkpoint?

8 Which proteins work together to regulate progression through the cell cycle?

9 What may happen when severe DNA damage is detected at a checkpoint?

10 What is the term for programmed cell death?

11 Which enzymes are central to the execution of apoptosis?

12 How does apoptosis usually affect nearby cells?

13 Cancer is best described as a disease involving:

14 A gene that normally helps stop excessive cell division is called a:

15 A mutation that increases cell division can contribute to the formation of a:

16 Which protein is commonly known for promoting apoptosis in response to serious DNA damage?

17 Many anticancer drugs work by targeting rapidly dividing cells. Why?

18 What does the term malignant mean when describing a tumor?

19 What is metastasis?

20 Which body systems can cancer cells use to travel to distant tissues?

21 A cell has completed DNA replication but has not yet entered mitosis. Which phase is it in, and what is its chromosome content relative to the original cell?

22 A population of cells shows a large increase in cells with duplicated DNA but no evidence of chromosome separation. Which cell-cycle transition is most likely blocked?

23 A mutation prevents sister chromatids from separating during mitosis. What is the most direct consequence?

24 Why does meiosis produce genetically different haploid cells more effectively than mitosis?

25 A species has chromosomes. How many chromosomes and chromatids are present in a cell at metaphase II of meiosis?

26 A cell with extensive DNA damage continues into S phase because a checkpoint protein is inactive. Which outcome is most likely?

27 A drug inhibits cyclin-dependent kinases required for the G1-to-S transition. What change would be expected in treated cells?

28 The spindle assembly checkpoint remains active because one chromosome is not attached correctly to spindle fibers. What does this checkpoint prevent?

29 A cell releases cytochrome from its mitochondria and activates initiator caspases. Which process is most likely occurring?

30 Which observation best distinguishes apoptosis from uncontrolled necrotic cell death in a tissue sample?

31 A death receptor on a cell binds its extracellular ligand and activates caspase-8. Which pathway has been initiated?

32 A cell acquires mutations that activate a growth-promoting signaling protein and inactivate a DNA-damage checkpoint. Why can these mutations cooperate in cancer development?

33 A tumor suppressor normally promotes cell-cycle arrest after DNA damage. Loss of this protein would most directly allow which behavior?

34 A cancer cell overexpresses the anti-apoptotic protein Bcl-2. Which treatment strategy could promote apoptosis by counteracting this change?

35 A tumor has a defective p53 pathway. Which anticancer approach may be especially useful if it restores p53 activity or induces cell death independently of p53?

36 A chemotherapy agent causes DNA damage, but tumor cells survive because they rapidly repair the lesions. Which combination may improve treatment effectiveness?

37 Which combination of properties most strongly indicates that a tumor is malignant rather than benign?

38 A tumor sample contains highly variable cell sizes, abnormal nuclei, and numerous atypical mitotic figures. What do these findings suggest?

39 A carcinoma enters nearby lymphatic vessels and is later detected in regional lymph nodes. Which step of metastasis has occurred?

40 A metastatic tumor cell exits a blood vessel and begins growing in a new organ. Which term describes the exit from the vessel?

41 A cell has completed DNA replication but has not yet entered mitosis. Which statement best describes its chromosome and DNA content relative to G1?

42 A diploid organism has . How many chromosomes and chromatids are present in each secondary spermatocyte immediately after meiosis I?

43 Nondisjunction occurs during meiosis II in one cell of a normally disjoining meiotic pair. Which gamete set is expected from that meiosis?

44 A mutation prevents inhibitory phosphorylation of Cdk1, but cyclin B synthesis and degradation remain normal. What is the most likely immediate consequence?

45 A cell sustains extensive DNA damage, but p53 is functional and p21 cannot be produced. Which outcome is most likely after the damage signal is detected?

46 A nondegradable securin mutant is expressed in an otherwise normal cell. Which event is most directly blocked?

47 A cell releases cytochrome after mitochondrial outer-membrane permeabilization, but Apaf-1 is genetically absent. Which response is most likely?

48 A tumor cell lacks functional caspase-8 but retains mitochondrial apoptotic signaling. Which death stimulus can still efficiently activate apoptosis through the intrinsic pathway?

49 Which observation most strongly distinguishes apoptosis from primary necrosis in cultured cells?

50 A mutation activates a receptor tyrosine kinase only when ligand-bound, but a second mutation eliminates its intracellular GTPase-activating protein. What is the likely signaling consequence?

51 A cancer cell has constitutively active PI3K and intact PTEN protein that cannot access the plasma membrane. Which prediction is most appropriate?

52 A lymphoma overexpresses the antiapoptotic protein BCL-2 but retains functional BAX, BAK, and caspases. Which treatment strategy most directly restores mitochondrial apoptosis?

53 A tumor lacks functional p53 but depends on an overactive antiapoptotic BCL-2 family protein. Which agent is most likely to kill it independently of p53 transcriptional activity?

54 A proteasome inhibitor causes accumulation of misfolded proteins and kills a cancer cell with intact apoptotic machinery. Which mechanism best explains selective sensitivity of some tumor cells?

55 Which combination most strongly supports a diagnosis of malignancy rather than merely increased cellular proliferation?

56 A tumor remains sharply circumscribed but contains cells with aneuploid genomes and abundant mitoses. Which conclusion is most justified?

57 A carcinoma cell survives in the circulation but fails to form a secondary tumor after extravasation. Which step of the metastatic cascade is most directly defective?

58 Inhibition of epithelial–mesenchymal transition reduces tumor-cell motility but does not affect primary tumor growth. Which metastatic event would be most directly impaired?

59 A metastatic clone expresses high levels of a matrix-degrading enzyme but cannot adhere to endothelial cells. Which process is most likely compromised?

60 A cell enters S phase with incompletely licensed replication origins because it bypassed the late-M and G1 licensing window. What is the most likely consequence?