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You are interested in studying different types of membrane transport. Initially you stain the cells for molecule X and Y and find that they are not expressed in the cell.  You then place the cells in an isotonic solution. You add molecule X to the solution and notice that it appears to bind temporarily to the surface of the cell and then later shows up inside the cell. You add molecule Y and notice that it instead rapidly transports from outside the cell to inside the cell, without binding to the cell surface, until the concentration is balanced. What kind of transport is being described for molecule Y?

Which question most precisely reflects Jagendorf and Uribe’s question?

Engelhardt draws a line between circumstances that are simply ___________ and those that are actually _______________

A study is done to determine the average tuition that Penn State undergraduate students pay per semester. One is asked how much tuition is paid for the fall semester in the following situation: A sample of 100 undergraduate Penn State undergraduate students is taken by organizing the students’ names by classification (freshman, sophomore, junior, or senior) and then selecting 25 students from each. What type of sampling is used?

What is the standard deviation for Group B?  

You have a planar bilayer with equal amounts of saturated and unsaturated phospholipids. After recording the degree of permeability of this membrane to glucose (there was some permeability), you increase the proportion of unsaturated, kinked phospholipids in the bilayer. What will happen to the membrane’s permeability to glucose?

Determine the type of sampling used: A medical researcher interviews every third cancer patient from a list of cancer patients at a local hospital.

Use this information for the next six questions. Cells were treated with ionomycin, a drug that causes cellular stress.  These cells were then tested to see if the stress reduced ATP levels.  Group A received no ionomycin.  Group B received ionomycin.  Group C received vanadate, a drug known to lower ATP levels.  The amount of ATP (mM) obtained from 4 samples per group were as follows:               Group A (mM ATP):              1.4, 1.6, 0.9, 2.0             Group B (mM ATP):              1.1, 0.0, 1.3, 1.5             Group C (mM ATP):              0.1, 0.2, 0.1, 0.3

In your words, what does the mode of a data represent? Give me a practical example/use when one would use the mode to describe a data set.

Phospholipid bilayer membranes are selectively permeable. What is meant by the phrase “selectively permeable”?