What factor prevents cells from becoming the size of blobs that consume city blocks in science fiction movies?

Answer 1

Cells are prevented from growing to enormous sizes due to the limitations imposed by their surface area-to-volume ratio. As a cell increases in size, its volume (which requires resources and waste removal) grows faster than its surface area (which controls the exchange of materials). This imbalance makes it difficult for larger cells to efficiently transport nutrients and waste, leading to cellular inefficiency and ultimately cell death. Additionally, the structural integrity provided by cellular membranes and cytoskeleton limits excessive growth.