Which of the following is NOT a function of membrane-embedded proteins?Choose one:A.  Membrane-embedded proteins can form the base of structures that extend out of the cell (such as flagella and pili).B.  Membrane-embedded proteins can store important inheritable information that is needed by the cell.C.  Membrane-embedded proteins can serve as receptors that detect specific environmental conditions.D.  Membrane-embedded proteins can import or export specific molecules through the membrane.

You have been asked to do a strucutural study to understand how increasing cell surface area affects cell size, cell shape and functions. What cell type would help you most efficiently observe the effects of increasing surface area?  Choices:  A. Monocytes from the blood serum. Monocytes are largely roughly spherical cells.  B. Red Blood cells from the bone marrow. The shape of Red blood cells is a biconcave disk and looks like a donut. C. Stem cells from skin. In this case assume a skin stem cell is flat and plate like.  D. Microvilli covered cells from the intestines. Microvilli are tiny hair like protrusions in the plasma membrane of intestinal cells that increase the absorption of nutrients in the intestines.

9. Recall that many cells have polarity (as in directionality, in this case). Consider the apical location of a particular protein (A) expressed in epithelial cells, illustrated in the figure above. Which type of defect described below is the most likely to cause the redistribution of that protein around the entire cell? A) A nonfunctional enzyme glycosylase. B) The deletion of a junctional protein. C) The truncation of a protein found in the extracellular matrix. D) A nonfunctional flippase. Answer: Explanation: apical plasma membrane lateral plasma membrane basal plasma membrane basal lamina protein A tight junction

Cancer is a complicated series of diseases characterized by over-proliferation of cells within a tissue. While in some instances the primary tumor is the ultimate cause of death, in many cases the primary tumor metastasizes, or moves, through the lymph system to invade other tissues. The migration of tumor cells requires changes in the adhesion properties of the cell that allow it to move and invade more readily.  There are several molecules involved in cell-to-cell connections and cellular architecture: laminins, matrix metalloproteinases, cadherins, and integrins. While mutations in genes that control the cell cycle or recognize DNA damage are the causes of tumor cell formation, tumor cell spread to other tissues may be caused by mutations in the genes the code for these extracellular proteins. The loss of cellular connections, cellular identification and signaling, and tissue structure may lead to the release of expanding tumor cells into the circulatory and lymphatic systems. Once…