#### Transcript LogApps Presentation

Aim: How do we apply
logarithms? (Part III)
Do Now: Solve for x:
log 2(x1) log 2(x 3)  3
A radioactive substance has a half-life of 3
years. After how long will 20% of the
substance remain?
• The energy, E, in kilocalories per gram
molecule, required to transport a substance
from the outside of a living cell to the inside is
given by:
E 1.4(log( C2 )  log( C1)
where C1 is the concentration outside the cell and
C2 is the concentration inside the cell.
The concentration of a particular substance inside
the cell is six times the concentration outside the cell.
How much energy is required to transport the
substance from the outside to the inside of the cell?
• The energy, E, in kilocalories per gram
molecule, required to transport a substance
from the outside of a living cell to the inside is
given by:
E 1.4(log( C2 )  log( C1)
where C1 is the concentration outside the cell
and C2 is the concentration inside the cell.
The concentration of a particular substance outside the
cell is eight times the concentration inside the cell. How
much energy is required to transport the substance from
the outside to the inside of the cell?