Anatomy of Caenorhabditis elegans

 

So here what can be made out of only 959 somatic (nongonadal) cells. Like us humans C. elegans  has a mouth and pharynx which constitutes a foregut. A pharyngeal-intestinal valve links the pharynx to the intestine and grinds food as it passes through. It has an intestine which, like us, extracts nutrition from the food it eats. A pharyngeal-intestinal valve (a total of 6 cells) links the pharynx to the intestine and grinds food as it passes through. Humans have a upper esophageal sphincter which performs the same function. And, finally, C. elegens  has a  proctodeum, like that of humans,  with anal grands, spincture and an anus through which feces is expelled. 

C. elegences has as a complete reproductive system wjich occupies about half of it body cavity. A few C. elegans are males (X chromosome only) but  99% are hermaphrodites (a pair of X chromosomes) and, like humans, with an ovary that produces eggs and a testis that produces sperm. And, like humans, reproduction is facilitated with  fertilized eggs. The hermaphroditic C. elegens has a fertility rate of  about 200 offspring but a hermaphroditic C. elegens inseminated by a male can give rise to a thousand or more offspring. And this is done in the course of a lifespan of only 10 to 15 days. In comparison, the global average fertility rate of humans is around 2.3 per woman over a lifespan of about 80 years.

Like humans, C. elegens depend upon gaseous diffusion of oxygen  from the environment. But being small in both size and number of cells, C. elegens has no need of specialized cells (lungs) for this to occur. Subsequently , C. elegens has no been of blood or heart to circulate food and oxygen to each cell. But usage of food and oxygen in the cells of human and C. elegens is exactly the same.

 Unlike humans, C. elegens has no arms and legs for mobility and moves by slithering like a snake. It does so with a total of 95 muscle cells (10% of all cells in its body). 

The structure of the tail of  C. elegans is anatomically different in  hermaphrodites and males and coincides with differences in the behaviors of  hermaphrodites and males. Yes, even the lowly C. elegens has its Adams and Eves ... just as do us humans. 

And, finally, we come to the neural systems of C. elegens but that is the most interesting subject for an entirely different post.