Question

For each of the following sentences, fill in the blanks with the best word or phrase selected from the list below. Not all words or phrases will be used; each word or phrase should be used only once.

Cells signal to one another in various ways. Some use extracellular signal molecules that are dissolved gases, such as ________, which can diffuse easily into cells. Others use cytokines, which bind to cytokine receptors. Cytokine receptors have no intrinsic enzyme activity but are associated with cytoplasmic tyrosine kinases called ______, which become activated on the binding of cytokine to its receptor and go on to phosphorylate and activate cytoplasmic transcriptional regulators called _________. Some intracellular signaling pathways involve chains of protein kinases that phosphorylate each other, as seen in the______signaling module. Lipids can also relay signals in the cell, as we observe when phospholipase C cleaves the sugar-phosphate head off a lipid molecule to generate the two small messenger molecules _____ (which remains embedded in the plasma membrane) and IP3 (which diffuses into the cytosol).

Options:
a) NO, JAKs, STATs, MAP kinase, diacylglycerol
b) cyclic GMP, Ras, SMAD, TGFβ, IP3
c) NO, JAKs, SMAD, cyclic GMP, MAP kinase
d) diacylglycerol, IP3, JAKs, Ras, STATs

Answer 1

Cells can use extracellular signal molecules like NO or cytokines to communicate with each other. These molecules bind to specific receptors on target cells, activating intracellular kinases called JAKs.

Step-by-step explanation:

Cells can communicate with each other using various methods. Some cells use extracellular signal molecules, such as nitric oxide (NO) or cytokines, to transmit signals. Cytokines bind to cytokine receptors, which are associated with cytoplasmic tyrosine kinases called JAKs. When cytokine binds to its receptor, it activates JAKs, which then phosphorylate and activate cytoplasmic transcriptional regulators called STATs. In addition, some intracellular signaling pathways involve protein kinases, like MAP kinases, which phosphorylate each other in a chain. Lipids can also transmit signals in the cell, as observed when phospholipase C cleaves a lipid molecule to generate diacylglycerol (DAG) and IP3 as second messenger molecules.