In pre-industrial period in England, most peppered moths had light coloration. During industrial revolution, many lichens died out and trees became blackened by soot from factories and interestingly, dark colored moths were predominantly seen. Which of the following observation is incorrect about above selection?

#Question id: 1506

#Unit 4. Cell Communication and Cell Signaling

An oncogene codes for a growth factor receptor that is constitutively active. Of the following statements about a culture of cells expressing this gene, which would you expect to be true?

#Question id: 1507

#Unit 4. Cell Communication and Cell Signaling

The genes responsible for cancer in RNA and DNA tumor viruses are:

#Question id: 1508

#Unit 4. Cell Communication and Cell Signaling

Of the following statements explaining how alterations of the ras gene cause cancer, which is true?

#Question id: 1509

#Unit 4. Cell Communication and Cell Signaling

Cells that are infected, damaged, or have reached the end of their functional life span often undergo "programmed cell death." This controlled cell suicide is called apoptosis. Select the appropriate description of this event on a cell's life cycle.

#Question id: 1510

#Unit 4. Cell Communication and Cell Signaling

Match the correct protein (Column I) with their function (Column II) during apoptosis.

#Question id: 1511

#Unit 4. Cell Communication and Cell Signaling

Most tumors induce the formation of new blood vessels that invade the tumor and nourish it, a process called angiogenesis. Following statements are regarding to angiogenesis.

A. Angiogenesis allow the tumor to increase in size and thus increase the probability that additional harmful mutations will occur.

B. Angiogenesis also facilitates the process of metastasis.

C. The VEGF receptors, which are tyrosine kinases, regulate several aspects of angiogenesis such as endothelial cell survival and growth, endothelial cell migration, and vessel wall permeability.

D. VEGF expression can be induced by oncogenes and by hypoxia, defined as a partial pressure of oxygen of more than 7 mmHg.

E. A transcription factor VEGF is activated in low-oxygen conditions and which binds to and induces transcription of the HIF-1 gene which  affect the probability of tumor growth by angiogenesis.

Which of the following statements are incorrect?