Energy is needed to transport a substance from outside a living cell to inside the cell. This energy is measured in kilo calories per gram molecule, and is given by
E = 1.4 log (C1) / (C2
where C1 represents the concentration of the substance outside the cell, and C2 represents the concentration inside the cell.
a) Find the energy needed to transport the exterior substance into the cell if the substance inside the cell is double the concentration outside the cell.
b) What is the sign of E if C1 < C2? Explain what this means in terms of the cell.
(Please show all your work to answer this question! Thank you so much!)
Replace C2 by 2C1
E = 1.4 log 2C1/C1 = 1.4 log 2
If C1<C2 then C1/C2 < 1 and the log is < 0
I assume negative energy needed means energy is released.
Oops - got the fraction upside down. 1.4 log 1/2
Me needs help
To answer these questions, we will use the given formula for energy needed to transport a substance into the cell:
E = 1.4 log (C1) / (C2)
a) To find the energy needed if the substance inside the cell is double the concentration outside the cell (C1), we can substitute the values into the formula.
Given: C2 = 2 * C1
E = 1.4 log (C1) / (2 * C1)
We can simplify this expression by canceling out C1:
E = 1.4 log (1) / 2
The log of 1 is equal to 0, so we can simplify further:
E = 1.4 * 0 / 2
E = 0
Therefore, the energy needed to transport the exterior substance into the cell when the concentration inside the cell is double the concentration outside the cell is 0 kilo calories per gram molecule.
b) To determine the sign of E if C1 < C2, we need to compare the concentrations.
If C1 < C2, it means that the concentration outside the cell is lower than the concentration inside the cell.
In the given equation E = 1.4 log (C1) / (C2), a negative value for E indicates that energy needs to be input into the system to drive the substance from lower to higher concentration.
Since C1 < C2 implies a negative value for E, it means that the cell needs to expend energy to transport the substance against the concentration gradient, moving from a lower concentration outside the cell to a higher concentration inside the cell. This process requires an input of energy to occur.