Use the Following Information to Answer the Questions Below

question 77

Multiple Choice

Use the following information to answer the questions below.
Human immunodeficiency virus (HIV) infects cells that have both CD4 and CCR5 cell surface molecules. The viral nucleic acid molecules are enclosed in a protein capsid, and the protein capsid is itself contained inside an envelope consisting of a lipid bilayer membrane and viral glycoproteins. One hypothesis for viral entry into cells is that binding of HIV membrane glycoproteins to CD4 and CCR5 initiates fusion of the HIV membrane with the plasma membrane, releasing the viral capsid into the cytoplasm. An alternative hypothesis is that HIV gains entry into the cell via receptor-mediated endocytosis, and membrane fusion occurs in the endocytotic vesicle. To test these alternative hypotheses for HIV entry, researchers labelled the lipids on the HIV membrane with a red fluorescent dye.

-What would be observed by live-cell fluorescence microscopy if the red fluorescent lipid dye-labelled HIV membrane fuses with the target cell plasma membrane?

• A)A spot of red fluorescence will remain on the infected cell's plasma membrane, marking the site of membrane fusion and HIV entry.
• B)The red fluorescent dye-labelled lipids will diffuse in the infected cell's plasma membrane and become difficult to detect.
• C)A spot of red fluorescence will move into the infected cell's cytoplasm.
• D)A spot of red fluorescence will remain outside the cell after delivering the viral capsid.
• E)Fluorescence microscopy does not have enough resolution to visualize fluorescently labelled HIV virus particles.

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Definitions:

Team Development

The process of improving the effectiveness of a work group through various stages, including forming, storming, norming, performing, and adjourning.

Failure

The inability to achieve a desired goal or objective despite effort.

Storming Stage

The second stage of team development characterized by conflict and competition as group members start to express differing opinions and vie for positions.

Cross-functional

Relating to or involving multiple departments or areas of expertise within an organization, aimed at achieving a specific goal.