You have isolated two mutations in the Lac operon that cause constitutive expression of Lac genes. You designate these mutants Lac1– and Lac2–. Making use of an F' that carries the Lac operon with the LacY gene mutated, you construct strains that you test for both ß-galactosidase activity and Lac permease activity with results shown below.

     

Classify each mutation as dominant or recessive and as cis- or trans-acting, giving the experimental result that allows you to arrive at each conclusion. Finally, deduce what type of Lac mutation best fits the properties of Lac 1– and of Lac 2–.

TLS Online TPP Program

#Question id: 24269

#Unit 4. Cell Communication and Cell Signaling

Which signaling proteins contains RGD motif & interact with integrins?

TLS Online TPP Program

#Question id: 24270

#Unit 4. Cell Communication and Cell Signaling

Integrins typically exhibit low affinities for their ligands, with

TLS Online TPP Program

#Question id: 24271

#Unit 4. Cell Communication and Cell Signaling

Integrins are involved in following processes, except:

a. Extravasation

b. Cell-to-cell adhesion

c. Cell migration

d. Receptors for certain viruses

e. Angiogenesis

f. Apoptosis

g. Necroptosis

TLS Online TPP Program

#Question id: 24272

#Unit 4. Cell Communication and Cell Signaling

.__________ are integrin-containing anchoring junctions that attach cells to elements of the underlying extracellular matrix.

TLS Online TPP Program

#Question id: 24273

#Unit 4. Cell Communication and Cell Signaling

Which of the following physiological function perform by integrins?

TLS Online TPP Program

#Question id: 24274

#Unit 2. Cellular Organization

Nucleosome DNA wraps around the histone protein 1.65 times, so create a writhe of –1.65 and so DLk should be -1.65. But when the change in linking number associated with each nucleosome was measured, the number was lower than this, approximately –1.2 for each nucleosome added. This discrepancy is referred to as the