Why do Individual cells tend not to grow very large?

Answer 1

Several factors limit cell size:

1. Diffusion doesn't work fast enough to transport materials into the interior of a too-large cell.
2. DNA can be transcribed fast enough to direct the formation of the larger number of proteins that will be needed in a too-large cell.
3. The surface area does not increase as quickly as the volume increases as a cell gets progressively larger. This means that a larger cell doesn't have enough plasma membrane to allow enough materials to go into and out of the cell. It's like having a bigger and bigger crowd trying to buy tickets, but not opening up very more ticket windows.

Answer 2

The cell membrane has to be strong enough to hold the insides, and permeable enough for the exchange of oxygen and nutrients and waste.
Also it doesn't have anything like a circulatory system to carry stuff around, which it would if it were bigger.
Actually, though, an ostrich egg is a single cell,,,but it's an embryo too, so I guess that's different.

Answer 3

Mostly it's the sa:volume ratio that prevents it - a cell needs a certain minimum area of membrane across which respiration can take place. That's why prokaryotic (bacterial) cells are so small - they have a large surface area in relation to their volume. Eukaryotic cells (i.e. the cells with nuclei that make up our bodies) are bigger because they have many mitochondria with a high sa:volume ratio,in which respiration occurs, doing away with the need for a large cell membrane sa:volume ratio.

Answer 4

because larger cells are very inefficient and require much more energy to actively perform the necessary functions of its life.

the smaller the cells the easier it si to maintain potential gradients across the entire cell so passive transport can be utilized without expending large amounts of energy to perform the same actions.

Answer 5

All cells have different shapes and different sizes depending on their function. Some are very big (human egg cell) versus small (red blood cell) versus long (neuron cell).