Category: 

What is the Largest Biological Cell?

Contrary to popular belief, an ostrich egg is not the largest biological cell.
Nerve cells in giraffes can be as long as the animal's neck.
Article Details
  • Written By: Michael Anissimov
  • Edited By: Bronwyn Harris
  • Last Modified Date: 20 October 2014
  • Copyright Protected:
    2003-2014
    Conjecture Corporation
  • Print this Article
Free Widgets for your Site/Blog
The CDC reported that eight foods, including peanuts and milk, account for 90% of food allergies.  more...

October 25 ,  1971 :  The United Nations expelled Taiwan and admitted China.  more...

The largest biological cell is often cited as the ostrich egg, which is about 6 inches (15 cm) long and weigh about 3 pounds (1.4 kg). This is a myth. There are at least several biological cells larger than an ostrich egg, despite the fact that even many scientists and laypeople believe the ostrich egg is indeed the biggest. The ostrich may actually be the heaviest cell, but this has not yet been tested.

Largeness refers to size, not weight, so the ostrich egg is definitely not the largest. The first type of cell larger than the ostrich egg are nerve cells in especially long animals, such as the Giant Squid and Colossal Squid, which may have nerve cells as long as 39 feet (12 m), about 80 times larger than an ostrich egg. Nerve cells have very long axons, enabling the brain to send signals to distant limbs almost instantly. In giraffes, the nerve cells may be several yards (meters) long, running the whole length of the animal's neck, and in humans, the longest nerve cells are about 4.9 feet (1.5 m), running from the base of the spine to the toes. So even the human body has biological cells larger than the ostrich egg.

Ad

One might argue that, in terms of volume, an ostrich egg is still the largest in comparison to nerve cells, which may be very long but exceedingly skinny, on the order of 10 microns or less. Even ignoring nerve cells, however, there is another type of cells larger than the ostrich egg: extremely large algae like Caulerpa, which may grow to 10 feet (3 m) in length or more, a single cell that may include up to 200 fronds.

Caulerpa is one among several other algae that superficially resemble vascular plants because of their branching structure. It is a type of cell that contains numerous nuclei, which may be part of the reason it is often overlooked when the award for largest biological cell is handed out. In Indonesia, certain species are eaten as the "sea grape," and they are said to have a peppery taste, and may be eaten fresh or with sugar.

Ad

More from Wisegeek

You might also Like

Discuss this Article

anon965211
Post 17

It is very cool to know that the ostrich has the largest cells in the world.

anon346437
Post 15

I think the confusion comes from high school biology - an egg is a very easy way to demonstrate what a cell looks like. It appears to have a cell wall, a cell membrane, and a nucleus. Obviously this is completely wrong - animal cells don't have cell walls so the shell isn't a good representation of this; albumen is nothing like the fluid within a cell, which contains ionic molecules to maintain fluid density and lots of organelles; and the yolk is nothing like a DNA containing nucleus.

Also, as an egg develops into a baby bird, it's not the egg that divides, it's a small embryonic cell within the egg - further demonstrating that the shell is not a cell wall and the yolk is not a nucleus. An egg is a useful tool for teaching kids, but an egg is definitely not a cell.

anon301946
Post 13

@anon585512: I completely agree.

anon287597
Post 12

Giant squid nerve cells might still win in volume; they are quite thick. What about coconuts? That's a big, heavy cell.

anon258865
Post 10

This is a common myth, but your reasoning for why it is false is not entirely correct. An ostrich egg contains a tiny egg cell, surrounded by supportive materials such as albumin, yolk and shell. Those supportive materials are not part of the egg. It is erroneous to think of an entire ostrich egg (or chicken egg, or snake egg, etc) as a cell. The cell part itself is tiny.

anon131569
Post 6

@chicada- Algae are not prokaryotic. Prokaryotic cells' defining characteristic is a lack of a nucleus. There are many other differences between prokaryotic and eukaryotic cells but the nucleus is the defining characteristic. Also, fertilized eggs (zygotes) would still fall in the category of eukaryotic cells because they are one cell. An embryo, on the other hand, is a collection of cells and thus not one cell.

anon123817
Post 5

A cell with multiple nuclei is often called a syncytium. An ostrich egg has just one nucleus. So too would a neuron. A better way to avoid confusion is to ask what is the largest cell by volume having a single nucleus. Is this the same as the largest cell with a single nucleus by length?

chicada
Post 4

@ aplenty- there are two types of cells in cellular biology, so there should probably be two different distinctions as to what the biggest biological cell is. A prokaryotic cell is self-replicating individual living unit that contains biomolecular parts bound together by a membrane. These cells are what biologists consider single celled organisms like bacteria and algae.

Eukaryotic cells on the other hand have a distinct nucleus and work with other eukaryotic cells as an individual unit in a multicellular organism. These types of cells would be the cells in our bodies, in plants, and in other animals. Eggs would fall into this category in its unfertilized state.

aplenty
Post 3

So what is the definition of a cell? What are the characteristics that define an ostrich egg or a spinal cord as a cell? What cell parts are necessary to qualify something as a cell?

anon58512
Post 1

It seems you are relating size to length alone. It would be interesting to know the volume of those very long cells. It could be that we have "winners" for length and the ostrich egg may still take the prize for volume.

Post your comments

Post Anonymously

Login

username
password
forgot password?

Register

username
password
confirm
email