Rosmana A.P | Science | Scientific Facts

There're many facts that human still don't know. Even, some of insignificant facts in this world are still unknown or forgotten. For example, a thing that small in size, but the biggest in other perspective. It is ovum cells.

cell is the structural and functional units that compose an organism. Cells were seen by Antonie Van Leeuwenhoek as the first man who see the cells through a microscope made by himself. Cells size around 0,1 µm (The smallest cells) to 7,1 inches. Many people think that cells are always small in size. But, this idea isn't entirely true. It is because some of cells are really big. For example, Reptile's and Bird's ovum. These organisms were ovipar organisms, which means they reproduce by laying eggs (which also known as ovum cells).


Reptile's and bird's ovum cells are large in size. It is because these organisms growth and develop in egg at the first time. Oppositely with mammals which growth and develop at the first time in it's mother's womb which gain some nutrition from it's mother, reptiles and birds gain their nutrition from albumin and yolk which already available in the egg. Albumin and yolk contain a lot of nutrition for the growth and developtment of the embryo which growth inside the egg. That's why their ovum cells are large. Maybe, their eggs are the biggest cells ever known.

This large cell consists of some parts. The outer part is egg shell which used to protect the albumin, yolk, and the embryo. This egg shell has a lot of pores on it. These pores help the transportation of gases, especially oxygen and carbon dioxide. So, the embryo won't die due to the lack of air. Inside the egg shell, there is albumin. This albumin contains a lot of nutrition like amino acids (protein), some vitamins, minerals, etc. At the blunt edge of egg, between the egg shell and albumin, there is an air cavity. This air cavity also helps the transportation of gases.

Around the center of the egg, there is a rounded yellow thing. This is the egg yolk which also contains nutrition for the embryo, usually fat. In this yolk, there is a cell which called germ plasm. Germ plasm is the cell that will growth and develop into a new organism.

One of the biggest cell in world is the ovum cell of ostrich. This cell can reach 7 inches in size. This size had make it become the largest cells that still exist until now.

Actually, there is another cell that was bigger than ostrich's ovum cell. It was the ovum cell of "Aepyornis maximus" or usually called The Elephant Bird. It's ovum cell may reach more than 34cm in size. It's egg is the largest cells ever known. Unfortunately, Elephant bird was already extinct around 2 centuries ago. If they were not extinct, The Elephant bird egg still the largest cell until now.

There are still a lot of things, even the insignificant ones that still unknown by humans. This world is only a small thing if it is compared with the knowledge and facts that scattered around this universe.