## Why are cells small?

Discussion of all aspects of cellular structure, physiology and communication.

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pjd822
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### Why are cells small?

Hi, I am taking a basic biology course and the instructor has challenged us with the question "Why must cells be small?" The question was raised in the context of the DNA synthesis stage of the cell reproduction cycle.
Thanks, Paul

Poison
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Bigger area=harder control
Also it's about the volume and surface area ratio. For optimum transport.
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david23
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yeah pretty much, and also smaller the easier for nutrients to defuse within the cell.

dr. dugmore
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Location: australia mate!!!!! bloody oath!! >lol<
look up "black perl" not the movie the organism, its pretty cool, and its only got 1 cell
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Dustfinger
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Cells are also small because many transports in the cytoplasm are achieved by diffusion. However, for a distance double the molecules need more than double the time. If cells were bigger, processes would be very very slow.

Tae Jun, Yoon
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### the examples about "Why is the cell small?"

I will give you some examples. Suppose that the shape of the cell is "sphere". then the volume of the sphere is (4/3)*pi*r^3, and the surface area of the sphere is 4*pi*r^2. the ratio of the volume to the area is (1/3)r. So as the value of r is increasing, the ratio is also increasing. Then the exchanging of materials through cell membrane is difficult.
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mehdi71000
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If you’re panting a huge picture the smaller your brush is the more detail you will have

If you had a 1mm diameter cell, for human to function the human would be very big. And I think if cells were big the cell walls in comparison would be very thin since a cell wall is 2 cholesterols thick if I’m not mistaken. just like an egg. an egg is a huge cell if you remove the shell the membrane is very easily puncture able. Reason 3 maybe you’re too big.

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