Studies of the endomembrane system often involve the use of a protein that can emit a green fluorescence (glow). A researcher wants to make a video of cell behavior, so she initially labels the outer nuclear envelope of a cell with the fluorescent tag and records a video for several hours. Later, she sees that the tag is part of a transport vesicle very close to the plasma membrane.
-The ability to stain protein molecules with a fluorescent dye would most clearly allow researchers to go beyond what they could previously detect with a microscope by allowing them to
A) detect ribosome activity.
B) detect when DNA is replicating.
C) distinguish a prokaryote from a eukaryote.
D) determine whether a cell had cilia or flagella.

Question

Quizplus · Accepted Answer

The fluorescent dye allows researchers to visualize the movement and behavior of proteins within the endomembrane system, which includes the activity of ribosomes. This goes beyond what could be detected with a microscope alone. The other options (B, C, and D) are not directly related to the endomembrane system or the use of fluorescent dyes to study it.

Studies of the Endomembrane System Often Involve the Use of a Protein