Brooklyn College explains that cells are small because they must have a large surface area relative to the amount of volume they contain to function properly. As a sphere grows larger, its volume increases much more rapidly than its surface area does. This presents logistical problems for the cell, as it tries to transport resources and products through a large volume without the resources available via a large surface.Continue Reading
As an example, a typical animal cell requires oxygen to survive. The size of the cell partially dictates the amount of oxygen it needs, while the surface area of the cell limits the amount of oxygen that can be absorbed at a time. Accordingly, when the size of a cell grows, its demand for oxygen and other resources rises at a rapid rate, while its capacity for absorbing oxygen increases more slowly. At some point, the size of the cell will cause the cell to divide or die, according to Brooklyn College.
Despite the limitations on cell size that are imposed by the surface-to-volume ratio, a 2013 study published in the journal Nature Cell Biology demonstrates that gravity also limits cell size. While gravity is a negligible force at very small scales, cells that attain about 1 millimeter in diameter must include structural elements to keep some organelles stable under the influence of gravity. Without such elements, cell components can lose their structural integrity.Learn more about Cells
The primary limitation on the size to which a single cell can grow is a mathematical principle called the surface to volume ratio. As the size of a three-dimensional object grows, its volume increases more rapidly than its surface does, which causes metabolic problems for cells. Additionally, the amount of cytoplasm the nucleus can contain and the structural limitations on the cell prevent them from being larger as well.Full Answer >
Some cells, including euglenas and various bacterial species, use tail-like projections called flagella to move across a surface. Other cells, including paramecia, use numerous hair-like projections called cilia for locomotion.Full Answer >
According to Santa Barbara City College, red blood cells' biconcave shape gives them a vastly greater surface area than a spherical cell of similar volume, which allows them to absorb oxygen more efficiently. Red blood cells achieve this shape by losing their nucleus and many other organelles during development. Red blood cells can neither reproduce nor replenish cellular machinery, and they die off in large numbers over time.Full Answer >
Chromatin forms chromosomes during cell division, packages DNA, reduces DNA volume, protects DNA from damage, and controls gene expression and DNA replication. Chromatin is a substance located in the nucleus of plant and animal cells consisting of RNA, DNA and other proteins.Full Answer >