Can some please explain Surface Area to volume ratios in ter

Can some please explain Surface Area to volume ratios in terms of the digestive system and absorption as well as neural activity?

Solution

Ans.) Basically, the surface of a cell is the site of exchange between its internal and external environment. This surface must permit adequate exchange to support the contents of the cell. As the size of an cell increases, eventually its volume and its surface area also increases, but its surface area to volume ratio decreases. For example, cubes demonstrate the surface area to volume ratio of a smaller size is larger than that of a large sized cube of similar shape. This ratio has the ability to limits how large cells can be. The higher the ratio, the faster the rate of diffusion into and out of the cells.

When a cell grows its rate of metabolism also increases at the same rate as its volume. This means that the rate of diffusion which provides the materials for metabolism must be increases proportionally with a cell’s growth. However, this can’t happen because a cell’s surface area increases at a much slower rate than its volume.

Neurons have a much higher surface area to volume ratio. As these cells need to be faster and more efficient at moving substances across the membrane because activities that are carried out in the brain (e.g. sending and receiving of a signal) must happen very rapidly in order for the body to function as best it can.