Which type of pumps inhibits digitoxin in the membranes of heart cells, leading to increased myocardial contraction?

#Question id: 1399

#Unit 4. Cell Communication and Cell Signaling

Loss-of-function mutations in which of the following genes typifies colorectal carcinomas?

a. myc              b. K-ras                       c. p53              d. APC

#Question id: 1400

#Unit 4. Cell Communication and Cell Signaling

Which property is shared by malignant tumor cells and transformed cells in culture?

a. reduced growth factor requirement                        b. attachment-dependent growth

c. loss of actin microfilaments                                    d. altered morphology

#Question id: 1402

#Unit 4. Cell Communication and Cell Signaling

Which of the following oncoproteins possess(es) protein kinase activity?

#Question id: 1403

#Unit 4. Cell Communication and Cell Signaling

Tumor-suppressor genes encode proteins with which of the following functions?

a. growth-promoting               b. growth-arresting                  c. pro-apoptotic

d. anti-apoptotic                      e. DNA repair

#Question id: 1404

#Unit 4. Cell Communication and Cell Signaling

Which of the following are transcription factors?

#Question id: 1405

#Unit 4. Cell Communication and Cell Signaling

A gain-of-function mutation in which of the following would have the same effect as a gain-of-function mutation in Ras?