The surface area-to-volume ratio of the cell.
The surface area-to-volume ratio of the cell.
No, bacterial cells are typically very small in size, ranging from about 0.5 to 5 micrometers in diameter. They are much smaller than most eukaryotic cells, such as human cells.
It's called the square-cube law. If an object (such as a cell) increases in size [say doubles] then its volume (or mass) goes up by the cube of the size, but its surface area increases only by the square of its size. Thus a doubling will produce a 4 fold increase in surface but an 8 fold increase in mass. Since cells depend on diffusion of molecules through its surface, it can outgrow its ability to acquire new materials (or to get ride of waste. This rule also limits the size of insects (actually all animals).
No. Nerve cells (neurons), for example, are very different in size and shape than epithelial or muscle cells. And don't forget the hen's egg and ostrich egg, each of which is a single cell.
they are blood vessels that reachout to the cells
they are blood vessels that reachout to the cells
Most cells are limited to a small size due to the need for efficient exchange of nutrients and waste products across their cell membrane. A smaller size allows for a higher surface area to volume ratio, which facilitates this exchange process. Additionally, a small size helps maintain internal cellular functions and processes within optimal ranges.
Very active cells have many mitochondria.Examples are cardiac cells,muscle cells etc.
In Very active cells like skeletal muscle cells,cardiac muscle cells
They have the potential to be very fast, but the fact that most are on short "tracks" limits them to slow speeds.
To have better control of metabolic activities in living cells there is optimum cytoplasm to nucleus size ratio called C/N ratio. To maintain this proportion the cells can not grow bigger than they are. However, to perform special functions cells may be of variable size. For example, fiber cells are very large and elongated, vessels are broader and perforated.
This is genetically determined. Genes act in very complex manner to keep the number of cells and size of the organ. How this happen is largely beyond the comprehension.