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 cells regulate expression of the pigment gene differently.The inactive cell removed the pigment gene from its DNA.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.The visible outcome identifies which molecular step failed.The similar appearance proves both cases have the same mutation.Two different mechanisms can produce the same visible outcome.
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 served only as a structural part of the cartilage.It instructed cartilage identity and nothing else.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 brake gene is still present but is repressed.The cell deleted the brake gene from every chromosome.The brake protein must be present at a high level.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?

   A stop signal and a growth signal are always the same molecule.Only the activated growth pathway can produce excess division.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 develops a specialized identity through gene regulation.A tissue spreads from its original site to a distant organ.A cell divides without any checkpoint or external signal.
7. Question 7 of 20

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

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

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

   These cells support a claim of local tissue invasion.The cells completed metastasis to a distant organ.The cells formed a benign tumor that cannot invade.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 timing and the cell's context can change the response.The early and late signals cannot be the same molecule.A signal has one fixed effect in every cell and at every time.The later cells must no longer contain receptors or genes.
10. Question 10 of 20

    Which description best defines cancer?

    An inherited condition that always appears in every family member.Any group of cells that divides faster than nearby tissue.Any tumor that can be seen in a medical image.Diseases with lost growth control and possible invasion or spread.
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 benign because no distant tumor was measured.The cancer has metastasized to every major organ.The tumor is invasive, and metastasis remains unproven.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?

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

    Bone cells deposit mineral while neurons transmit electrical signals. Which principle explains the difference?

    Each tissue receives a new genome after birth.Gene use builds specialized structures.Cell function is unrelated to cell structure.Neurons have DNA but bone cells do not.
14. Question 14 of 20

    Blood glucose rises and insulin helps cells take up glucose, lowering the level. Which description fits?

    Local invasion into a blood vesselNegative feedback restores the rangePositive feedback that raises glucose furtherCell differentiation into a new tissue
15. Question 15 of 20

    Neural crest cells reach the face but cannot attach to the correct matrix. What is the most direct prediction?

    The cells have proven distant metastasis.The cells complete normal organization anyway.Every cell in the embryo becomes neural crest.Local tissue organization may be disrupted.
16. Question 16 of 20

    Two patients have similar swallowing difficulty, but one has a muscle problem and the other has a structural opening. What does this show?

    Swallowing difficulty identifies one diagnosis by itself.Muscle and structure have no effect on function.One symptom can have different anatomical causes.The patients must have the same gene variant.
17. Question 17 of 20

    A developing duct fails to hollow because selected center cells do not die. Which process is disrupted?

    Metastatic spreadAntibody productionApoptosisPositive feedback
18. Question 18 of 20

    A growing tumor becomes limited by low oxygen, then recruits new vessels. How do the vessels help?

    They supply oxygen and nutrients.They remove all mutations from the tumor.They prevent any cell from entering the circulation.They turn every malignant cell into a benign cell.
19. Question 19 of 20

    A tumor grows slowly but crosses the tissue boundary. How should it be classified?

    Nonliving because it crosses a boundaryMalignant, because it invadesBenign because its growth is slowNormal because it uses body nutrients
20. Question 20 of 20

    Colon cancer cells are found in the liver. Which name is anatomically correct?

    A new primary liver cancerA benign liver tumorMetastatic colon cancerA liver infection