can someone tell me how big a cell in the human body actually is? i know theyre tiny, but i need a measurement doing a bit of a project here and need some help
The point about the nerve cells is kind of bogus, because most of that distance (not 3m, but can get as long as 1m) is the long, slender axon of the cell. The cell body is still small, somewhere between 10-100 microns across. The largest cell in the human body is the ovum, which is visible with the naked eye. It's about the size of a period in a 10 or 12 point font.
ok, im meaning red blood cells, white blood cells, and do viruses have cells or what, if so how big are they generally
The axon is still part of the cell of the cell body in that it is enveloped by the cell membrane and has cytoplasm inside. From the quote I gave you: Human cells also display a variety of sizes, from small red blood cells that measure 0.00076 mm (0.00003 in) to liver cells that may be ten times larger. Viruses don´t have cells, are not cells even. Just a protein coat with some genetic material inside, with some variation on this theme. http://web.ukonline.co.uk/webwise/spinneret/microbes/virus.htm
ive got a bio book here. these are relative sizes: Eukaryotic: 10-100 um Prokaryotic: 1-5 um Nucleus: 10-20 um Chloroplast: 2-10 um Mitochondria: .5-5 um HIV (Large Virus): 100 nm Ribosome: 25 nm Cell membrane: 7.5 nm thick DNA double helix: 2 nm thick H atom: .1 nm largest known bacterium found in fish around australia, about 1 mm in length each sap filled vesicle of an orange is one cell :m:
Hypatia alluded to this in a post above. Referring to the size of neurons is a bit subjective because neurons extend long thin axons that are often many times the length of the cell body itself. Descriptions of some neurons being “1 meter” in length are describing the total length of some of the longest known axons, not the size of the actual cell body. Neuronal cell body sizes are a very average 10 to 20 microns. <center><img src="http://inside.salve.edu/walsh/neuron.jpg"></center>
An ostrich egg is a really big cell. For humans, the largest somatic cell is the megakaryocyte in the bone marrow.
The size of a cell has to do with the ratio of surface area to volume. This determines how large they can get. Most plant and animal cells are about 10 to 50 nanometers in diameter
Nanometers? I think you mean micrometers. As has been listed above, most animal cells are around three orders of magnitude bigger than that (~10 to 50 um). Plant cells, in general, are bigger again. <P>