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Question 1

• Stepwise Tumor Developmentm:
  Neoplasm develops as the result of multiple genetic and epigenetic changes that occur over a relatively _________.

Answer 1

long time course

Question 2

In all species these tumors develop through the same sequence of steps:

Answer 2

1. Epidermal hyperplasia
2. Carcinoma in situ
3. Invasion carcinoma

Question 3

-stepwise:
1. The first step is initiation

Answer 3

Introduction of irreversible genetic change into basal cell by action of initiator.

Question 4

________ chemicals or physical carcinogens that damage DNA.

Answer 4

Initiators

Question 4

Mutation induction requires not only introduction of DNA lesion, but also

Answer 4

mispairing of DNA lesion during DNA replication to produce an altered complementary DNA strand.
- Thus at least a single round of DNA replication is necessary for fixation of genetic change to occur.

Question 5

Initiated cells appear morphologically _______ and may _______ quiescent for many years.

Answer 5

normal, remain

Question 6

• stepwise
  The second stage of tumor development is promotion:

Answer 6

• refers to the outgrowth of initiated cells in response to selective stimuli.

Question 7

selective stimuli termed as

Answer 7

Promoting agent or promoter

Question 8

Example:promotion

Answer 8

the skin irritant croton oil is an effective skin tumor promoter.

Question 9

Complete carcinogen

Answer 9

Initiator and promoter react as both ( initiation, promotion )

Question 10

Because promoters are not mutagenic, their effect are usually _________

Answer 10

reversible

Question 11

• stepwise
  The final stage of tumor development is progression.

Answer 11

conversion of a benign tumor to an malignant tumor and to a metastatic tumor.

Question 12

Malignant conversion represent an ________ change in nature of developing tumor.

Answer 12

irreversible

Question 13

Karyotypic instability in tumor cells and increasing tumor cells heterogeneity are hallmarks of

Answer 13

Progression

Question 14

Development of squamous cell carcinoma:

Answer 14

1. A focus of epidermal hyperplasia.
2. This develops into a papilloma, a benign.
3. As the papilloma undergoes conversion into a malignant squamous cell carcinoma.
4. fully exposed squamous cell carcinoma