Top 10 unbelievable historical concurrencies. A zygote is a single cell which has formed as the result of the merging of an egg cell and a sperm cell. In other words, it's a fertilized egg, with the potential to develop into a living organism.
Gastrovascular system of the flatworm Dugesia, colored yellow. The gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Cnidaria (including jellyfish and corals) and Platyhelminthes (flatworms). The cavity may be extensively branched into a system of canals. In cnidarians, the gastrovascular system is also known as the coelenteron, and is commonly known as a blind gut or blind sac, since food enters and waste exits through the same orifice.
The pharynx is a fibromuscular cavity that is situated within the throat and is located posterior or at the back of the nasal and the oral cavities.This structure is also found posterior to the larynx.he pharynx is a fibromuscular cavity that is situated within the throat and is located posterior or at the back of the nasal and the oral cavities.