Why can't cells just keep getting bigger? What is the largest single cell?
- JazSincLv 71 month agoFavorite Answer
They can keep getting bigger, but there are engineering problems to overcome.
1. The surface area to volume ratio. For a cell, there has to be enough surface area for gas exchange, metabolic waste removal, acquiring of nutrients.
A large cell, such as slime molds during part of their life cycle, are pretty much flat with wrinkles, so there's lots of surface area. That slime mold could be tens of centimeters across.
2. The distance between the DNA and the cytoplasm. The cytoplasm is going to need RNA constantly to make the proteins it needs to keep the metabolism going. In a big cell, you would expect the distance between the DNA and the farthest reaches of cytoplasm to be longer than in a smaller cell.
The aforementioned slime molds overcome that obstacle by being multinucleated. I would expect other large eukaryotic single cells to be similarly multinucleated. I would expect large "prokaryotic" cells to have multiple copies of the "chromosome."
> What is the largest single cell?
Those slime molds, as mentioned, can be tens of centimeters across.
Caulerpa taxifolia, a marine alga, might also qualify. Or, you might decide not to qualify it as "acellular" instead.
Both of these examples are more like multicellular things that have somehow lost their internal cell membranes, than things that have evolved their large size from small single-celled ancestors.
- οικοςLv 71 month ago
The largest single cell is an ostrich egg.
- ZirpLv 71 month ago
As they grow bigger, volume grows faster than surface. At some point, there's not enough surface to take in and move out enough stuff for the needs of the interior.
the biggest human cell is the ovum
- babyboomer1001Lv 71 month ago
They do get bigger. They multiply at three states in our growing years. That's why it is so hard for some people to lose weight. If they were stuffed as a child, their cells multiplied then, so with many more cells than they should have, losing weight is very difficult for them. Most of the time, and after the growing years, they just grow bigger when we eat too much and get fatter.