The stages in the formation of the symbiotic relationship between the nitrogen-fixing bacteria and their host, Arrange the given statements of symbiotic association in a stepwise manner;

 a) Migration of the bacteria toward the roots of the host plant by a chemotactic response mediated by chemical attractants

b) NodD with the flavonoids bind with the Promoter region of  highly conserved the nod box

c) These attractants activate the rhizobial NodD protein,

d) The chemical attractants especially (iso)flavonoids and betaines, secreted by the roots

e) Binding of the activated NodD to the nod box induces transcription of the other nod genes

 Which of the following from the above statements are correct arrangement of symbiosis?

#Question id: 24204

#Unit 4. Cell Communication and Cell Signaling

#Question id: 24203

#Unit 4. Cell Communication and Cell Signaling

#Question id: 24202

#Unit 4. Cell Communication and Cell Signaling

#Question id: 1388

#Unit 4. Cell Communication and Cell Signaling

When Lucifer yellow, a small dye, is injected into a neuron of the retina, neighboring neurons become rapidly labeled. If the retina is incubated in dopamine prior to Lucifer yellow injection, only the injected neuron becomes labeled. These findings suggest which of the following?

I. Neurons of the retina communicate via gap junctions.

II. Dopamine is transferred between cells via gap junctions.

III. Dopamine decreases the permeability of gap junctions.

#Question id: 1387

#Unit 4. Cell Communication and Cell Signaling

The ability of a population of fibroblasts to migrate along the surface of a tissue culture dish depends on adhesion between the cell surface and the extracellular matrix molecules coating the dish. The dish is coated with laminin, and the only cell-surface protein capable of binding laminin is a cell-adhesion protein called an integrin. Integrins are integral plasma-membrane proteins that function as heterodimers. Under these conditions the rate at which a fibroblast can migrate along the laminin coated culture dish is proportional to the strength of adhesion between the cell and the laminin substrate. The table below lists the rate of cell migration observed for fibroblasts genetically engineered to generate the indicated phenotypes. Microinjection into the cytoplasm of a wild. type cell of a solution of a synthetic peptide possessing the same sequence as the integrin beta subunit cytoplasmic domain would be expected to yield an average fibroblast-cell migration rat

#Question id: 1386

#Unit 4. Cell Communication and Cell Signaling

The ability of a population of fibroblasts to migrate along the surface of a tissue culture dish depends on adhesion between the cell surface and the extracellular matrix molecules coating the dish. The dish is coated with laminin, and the only cell-surface protein capable of binding laminin is a cell-adhesion protein called an integrin. Integrins are integral plasma-membrane proteins that function as heterodimers. Under these conditions the rate at which a fibroblast can migrate along the laminin coated culture dish is proportional to the strength of adhesion between the cell and the laminin substrate. The table below lists the rate of cell migration observed for fibroblasts genetically engineered to generate the indicated phenotypes. One explanation for the effect of overexpression of the cytoplasmic domain of the integrin beta subunit is that this domain normally functions to bind a cytoplasmic factor necessary for integrin function. Which of the following would be the most informative experiment to identify the cytoplasmic factor?