Question : 6) What is a tumor suppressor gene 7) What is an oncogene : 2134333

6) What is a tumor suppressor gene?

A. A gene associated with tumor formation when its product does not function.

B. A gene associated with tumor formation when its product functions normally.

C. A gene that accelerates the cell cycle and leads to uncontrolled cell growth.

D. A gene that codes for a transcription factor involved in tumor formation.

7) What is an oncogene?

A. A gene associated with tumor formation when its product does not function.

B. A gene associated with tumor formation when it is inappropriately activated.

C. A gene that inhibits cell growth when its product functions normally.

D. A gene that codes for a transcription factor involved in tumor formation.

8) The c-src proto-oncogene encodes a membrane-associated, nonreceptor tyrosine kinase. The v-src oncogene product differs from c-Src in what way?

A. Because of amino acid substitutions in the C-terminus, the v-Src protein remains in the active conformation and dephosphorylates target proteins.

B. Because of amino acid substitutions in the C-terminus, the v-Src protein remains in the active conformation, binds to target genes and activates their expression.

C. Because of amino acid substitutions in the C-terminus, the v-Src protein remains in the inactive conformation and cannot phosphorylate target proteins.

D. Because of amino acid substitutions in the C-terminus, the v-Src protein remains in the active conformation and phosphorylates target proteins.

9) The c-myc proto-oncogene encodes a

A. helix-loop-helix transcription factor

B. nonreceptor tyrosine kinase

C. GTP-binding protein

D. secreted growth factor

10) What would be the effect on cell growth if the retinoblastoma protein (pRB) remained phosphorylated?

A. pRB would prevent E2F from binding to regulatory elements in S phase-specific genes, resulting in an inhibition of cell growth.

B. The E2F complex would continue to stimulate S phase-specific genes, resulting in an

inhibition of cell growth.

C. The E2F complex would continue to stimulate S phase-specific genes, resulting in

unrestrained cell growth.

D. Cell growth would be normal because pRB is a phosphoprotein.