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When we think of membrane transport, we often think first of ATP-dependent, active mechanisms. However, it is also true that passive diffusion of ions and molecules plays an important role in many physiological systems. For each of the following situations, indicate whether ACTIVE or PASSIVE membrane transport is used, or if BOTH forms of transport may be used.

Match the descriptions to the terms in the list below. Assume nothing: choices may be used more than once, or not at all. More than one listed answer may be correct.

Select the equations used when solving the above problem:  (The original problem: A box of 10.0 cm x 10.0 cm x 10.0 cm contains 1.2 x 105 Pa of N2 gas molecules at 25°C.  The mass of one N2 molecule is 4.68 x 10-26 kg and its molar mass is 28.0-g.  Assume all the molecules collide with the container walls with its rms speed in a head-on fashion and all the collisions are perfectly elastic, estimate the amount of molecules striking one side of the container wall in 10 seconds? )

Select the equations used when solving the above problem:  (The original problem: An underground gasoline tank can hold V gallons of gasoline at 52.0°F.  The tank is being filled on a hot day by a truck when the outdoor temperature is T°F.  How many gallons of gasoline from the truck can be poured into the tank? Assume the temperature of the gasoline quickly cools from T°F to 52.0°F upon entering the tank. )

Select the equations used when solving the above problem:  (The original problem: Determine the elongation of the rod in cm for the rod shown in the figure if it is under a tension of {T} ✕ 103 N.)

For a given thermopane window of {A} m2 and R value of {R} m2 oC/W,  determine the amount of heat loss through this window in one hour if the temperature difference between inside and outside of the window surfaces is 21 oC.  Express your answer in kJ.

Select the equations used when solving the above problem:  (The original problem: m-g of ice cubes at 0°C is added to 300-g of water at 25°C.  What is the final equilibrium temperature of the mixture in oC?  Assume that no energy is lost in this process and ignore the amount of heat absorbed by the container. )

For a physics experiment, a solid cube is suspended from a spring scale. The gravitational force exerted on the cube is 0.714 N as measured when the object is suspended from a spring scale. When the suspended cube is submerged in water (ρ = 1000 kg/m3), the scale reads 0.450 N.   Determine the buoyant force (in units of N) acting on the cube based upon the force measurements.

 {m}-g of ice cubes at 0°C is added to 300-g of water at 25°C.  What is the final equilibrium temperature of the mixture in oC?  Assume that no energy is lost in this process and ignore the amount of heat absorbed by the container.  Enter your unit as “C”.

 The first branches of the bronchial tree  is/are called: