White-breasted nuthatches and Downy woodpeckers both eat insects that hide in the furrows of bark in hardwood trees. The Downy woodpecker searches for insects by hunting from the bottom of the tree trunk to the top, while the White-breasted nuthatch searches from the top of the trunk down. These hunting behaviours best illustrate which of the following ecological concepts?

#Question id: 1396

#Unit 4. Cell Communication and Cell Signaling

Trks are:

a. endonucleases.        b. transmembrane receptors.   c. proteases.     d. protein kinases.      

#Question id: 1397

#Unit 4. Cell Communication and Cell Signaling

The vertebrate equivalent of CED-9 is:

#Question id: 1398

#Unit 4. Cell Communication and Cell Signaling

Which of the following properties is (are) characteristic of a benign tumor?

a. well differentiated              b. localized to tissue of origin             c. metastatic               

d. promotes angiogenesis        e. surrounded by a fibrous capsule

#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?