Development to Cancer Post-test

0 of 20 answered

1. Question 1 of 20

   Two skin cells contain the same pigment gene, but only one cell makes the pigment protein. Which explanation is best?

   The inactive cell removed the pigment gene from its DNA.The cells regulate expression of the pigment gene differently.The active cell absorbed the finished protein from nearby blood.The two cells must have entirely different chromosome numbers.
2. Question 2 of 20

   Two developing palates fail to fuse and look similar. In one, a signal is missing. In the other, cells cannot respond to the signal. What follows?

   The signal must be unrelated because both cases look alike.Two different mechanisms can produce the same visible outcome.The similar appearance proves both cases have the same mutation.The visible outcome identifies which molecular step failed.
3. Question 3 of 20

   Cells already committed to cartilage stop migrating when Signal X is removed. A different motility signal restores migration, and the cells still become cartilage. What role did Signal X most likely play?

   It instructed cartilage identity and nothing else.It served only as a structural part of the cartilage.It permitted the migration, and did not set cartilage identity.It permanently changed every gene in the cells.
4. Question 4 of 20

   A cell still contains a working growth-brake gene, but regulatory proteins keep the gene silent. Which statement is most accurate?

   The cell deleted the brake gene from every chromosome.The brake protein must be present at a high level.The brake gene is still present but is repressed.The brake gene has become an oncogene.
5. Question 5 of 20

   One cell line activates a growth pathway. Another loses a stop signal. Both divide too often. Which principle fits best?

   Only the activated growth pathway can produce excess division.A stop signal and a growth signal are always the same molecule.The two cell lines must contain identical mutations.Different disrupted pathways can converge on the same outcome.
6. Question 6 of 20

   What is differentiation?

   A cell replaces its DNA with genes from a nearby tissue.A cell divides without any checkpoint or external signal.A tissue spreads from its original site to a distant organ.A cell develops a specialized identity through gene regulation.
7. Question 7 of 20

   During normal development, cells between forming fingers undergo programmed death. What does this show?

   The cells died because every developmental signal failed.Development builds structures only by adding more cells.Programmed death is evidence that the embryo has cancer.Development can sculpt tissue through programmed cell removal.
8. Question 8 of 20

   Tumor cells reduce adhesion and move through a remodeled extracellular matrix into nearby tissue. What does this evidence support?

   The cells formed a benign tumor that cannot invade.These cells support a claim of local tissue invasion.The cells completed metastasis to a distant organ.The cells changed every gene into an oncogene.
9. Question 9 of 20

   The same signal promotes cell division early in development but promotes differentiation later. Which explanation is best?

   The later cells must no longer contain receptors or genes.A signal has one fixed effect in every cell and at every time.The early and late signals cannot be the same molecule.The timing and the cell's context can change the response.
10. Question 10 of 20

    Which description best defines cancer?

    An inherited condition that always appears in every family member.Diseases with lost growth control and possible invasion or spread.Any tumor that can be seen in a medical image.Any group of cells that divides faster than nearby tissue.
11. Question 11 of 20

    A biopsy shows abnormal cells crossing into nearby tissue. No distant sites were tested. Which conclusion stays within the evidence?

    The tumor is invasive, and metastasis remains unproven.The cancer has metastasized to every major organ.The tumor is benign because no distant tumor was measured.The biopsy proves which treatment will work best.
12. Question 12 of 20

    A targeted drug kills most cells in a tumor, but a small cell group lacks the target and survives. What is the best prediction?

    All tumor cells will remain equally sensitive to the drug.The surviving cells will automatically become normal tissue.The resistant group of cells may expand after treatment begins.The drug will add the missing target to every surviving cell.
13. Question 13 of 20

    A pathogenic variant appears in blood, skin, and tumor samples from one person. Which origin is most plausible?

    A tumor-only somatic variantA sequencing result that proves metastasisA mutation acquired from a classmateA germline variant
14. Question 14 of 20

    Two people carry the same cancer-risk variant, but only one develops cancer. What is the best explanation?

    The variant has no biological effect.The unaffected person cannot develop any cancer.Cancer depends on additional changes and context.The affected person caught cancer from someone else.
15. Question 15 of 20

    A gene normally promotes growth only when a signal is present. A mutation locks it active. What has it become?

    A DNA-repair geneAn oncogeneA tumor-suppressor geneA structural chromosome
16. Question 16 of 20

    A cell loses both working copies of a gene that normally stops division after DNA damage. What is the likely effect?

    The cell becomes immune to every treatment.The cell loses all receptors at once.Damaged cells may keep dividing.The cell repairs every mutation immediately.
17. Question 17 of 20

    Biomarker testing finds no Target T in a tumor sample. What treatment inference is most defensible?

    Target T therapy is less likely to help.Every other treatment will succeed.The tumor cannot contain any genetic variation.The patient has no cancer of any kind.
18. Question 18 of 20

    A localized tumor is treated with a focused high-energy beam. Which treatment is described?

    Radiation therapySystemic chemotherapyGenetic counselingAntibiotic therapy
19. Question 19 of 20

    A tumor hides a signal that immune cells use to identify abnormal cells. Which treatment idea best matches the mechanism?

    Restore immune recognition of the tumorRemove every normal immune cellIncrease tumor nutrient supplyTreat the tumor as a bacterial infection
20. Question 20 of 20

    Two tumor cell groups use different survival pathways. Why might a combination treatment be considered?

    It may block more than one escape route.Combinations guarantee no side effects.Two drugs make all tumor cells genetically identical.One drug always reaches every pathway equally.