Individuals with the disorder xeroderma pigmentosum are hypersensitive to sunlight, and mutations to the DNA in their skin cells are left uncorrected. Why are the mutations not corrected in individuals with this disorder?

#Question id: 1162

#Unit 4. Cell Communication and Cell Signaling

Diacylglycerol (DAG) formation aids in cell signaling by:

#Question id: 1163

#Unit 4. Cell Communication and Cell Signaling

β-blockers inhibit an adrenergic receptor found on many cell types in the body, including heart cells. Patients who have arrhythmias (irregular heartbeats) most likely benefit from what downstream action of these drugs?

#Question id: 1164

#Unit 4. Cell Communication and Cell Signaling

Calmodulin:

#Question id: 1165

#Unit 4. Cell Communication and Cell Signaling

DAG activates:

#Question id: 1166

#Unit 4. Cell Communication and Cell Signaling

In muscle, glycogen phosphorylase kinase can be activated by nerve stimulation even in the absence of hormonal signals. Nerve stimulation alone results in activation of glycogen phosphorylase kinase as a result of:

#Question id: 1167

#Unit 4. Cell Communication and Cell Signaling

After a meal, when blood glucose rises, circulating insulin binds to insulin receptors on various cell types and reduces blood glucose levels by:

a. fusion of intracellular vesicles containing GLUT4 glucose transporters with the plasma membrane.

b. stimulation of the conversion of glucose to glycogen.

c. inhibition of glucose synthesis from smaller molecules.

Which of the following combination is correct?