the most widely distributed plasma-membrane effector protein in cells is adenylyl cyclase true or false?

The sodium Na+/Glucose symport moves sodium and glucose across the plasma membrane. A) Describe was is meant by a symport. Include in your answer whether a symport is an example of a channel protein or a carrier protein. B) Why does the Na+/Glucose transporter work in only one direction? C) Describe how glucose can be both actively and passively transported into an out of the same cell. Include in your description how localization of transport proteins allows for these two different types of transport to occur in the same cell.

Define anterograde axoplasmic transport. Why is this type of axonal transport necessary in most neurons? And, briefly describe the molecules involved in facilitating anterograde transport 2

What causes an alteration in cell resting membrane potential? What signs and symptoms would you expect to identify when your patient has an altered RMP?

Cystic fibrosis (CF) is a genetic disorder caused by mutations in the CFTR (cystic fibrosis transmembrane-conductance regulator) gene, which encodes the CFTR protein. The cells of the lining of the lungs contain high levels of the CFTR protein in their membranes. Normally, CFTR contains a chloride ion channel, which permits chloride ions to pass from inside the cells to the cells’ surfaces. The surface chloride ions are able to attract water in the lungs, allowing for the formation of a water layer on the cells’ surfaces. This thin water layer is necessary to allow the cilia, the tiny hairs on the surface of the lining cells to move back and forth easily. This motion permits the removal of mucus from the lungs. A particular error in the CFTR gene results in the replacement of the amino acid Phe with Ser at residue 508 of the CFTR protein. Individuals afflicted with CF most often experience the presence of thick, dry and sticky mucus in the lungs, leading to chronic infections and…

When Hedgehog binds to Patched, this not only activates the signaling pathway but alsoactivates the receptor-mediated endocytosis of Patched, so there is less Patched on the plasmamembrane to inhibit Smoothened. a. Outline the steps of receptor-mediated endocytosis, including the roles for each proteininvolved. Hint: if your answer does not include the protein dynamin, you are notproviding enough detail. b. What will happen to Patched after it enters the cell via receptor-mediated endocytosis?Assume that Patched is not recycled back to the plasma membrane.

One form of anemia results when individuals have a deficiency in the enzyme phosphatidylinositol glycan A (PIGA). This enzyme is required for the membrane attachment of proteins anchored by glycolipids to the plasma membrane, using what is called a ‘GPI-linkage.’ Included in the group of GPI-linked cell surface proteins is DAF/CD55. These individuals become anemic because: DAF/CD55 prevents the lysis of red blood cells by infecting pathogens. DAF/CD55 normally prevents the spleen from clearing healthy red blood cells from the circulation. In the absence of PIGA, the red blood cell membrane is bare of proteins allowing increased access of complement activating proteins to attach to the cell membrane. DAF/CD55 is a complement inhibitory protein that inactivates any C3 convertase that may form on host cell surfaces. In the absence of PIGA, red blood cells are unable to synthesize high levels of hemoglobin.

According to the “Hawaiian Punch” principle, different compartments of the secretory and endocytic pathways are topologically equivalent to each other and to the extracellular space. Explain how vesicular transport generates this topological equivalence. These compartments are topologically equivalent because molecules can move between them without having to move out of the cell. Transport vesicles cause this “topological equivalence” because they are responsible for the actual movement of the molecules mentioned above. They break off from one compartment, carrying the necessary molecules, and then fuse to its targeted compartment; thus, making the compartments topologically equivalent.  During mitosis in mammalian cells, the nuclear envelope breaks down into vesicles. Are the topological properties of the cell altered by this event? Justify your answer.

Describe serine-threonine membrane receptor.

Mark and label the locations of pluripotent stem cells, adult/tissue stem cells and somatic cells in the diagram to the right. What potency is the red cell on top?