Question

A liver cell has a volume of 5000 μm3. Its total membrane area, including the inner membranes lining organelles as well as the cell membrane, is 110,000 μm2. A cell in the pancreas that manufactures digestive enzymes has a volume of 1000 μm3 and a total membrane area of 13,000 μm2. Which cell is probably more efficient in carrying out activities that require extensive membrane surfaces? Why?

Answer 1

Answer:

The liver cell, since it has a higher surface to volume ratio will be more efficient in carrying out activities that require extensive membrane surfaces such as solute transport.

Explanation:

The cell surface area to volume ratio is important in order to determine the efficiency of the cell in carrying out its metabolic activities. The surface area of a cell is bounded by the cell membrane whose function in addition to many others is to let nutrients into the cell and let waste out of the cell. The rate of activity of a cell depends on its volume. The larger the volume the more the active the cell is. Since volume increases much more when compared to area, the ratio of the surface area of a cell to its volume becomes smaller with increase in volume of the cell.

Considering the liver cell and the pancreas cell in the question, the cell's surface area to volume ratio is given as follows:

Liver cell: volume = 5000 μm³; area = 110000 μm²

surface area to volume ratio = 110000 / 5000  = 22 : 1

Pancreas cell : volume = 1000 μm³ ; area = 13000 μm²

Surface area to volume ratio =13000 / 1000 = 13 : 1

The liver cell, since it has a higher surface to volume ratio will be more efficient in carrying out activities that require extensive membrane surfaces such as solute transport.