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 gastrovascular cavity is a structure found in primitive animal phyla. It is responsible for both the digestion of food and the transport of nutrients throughout the body. The cavity has only one opening to the environment. Food goes in and waste comes out that same opening, making it a two-way digestive tract.nidaria. The gastrovascular cavity in Cnidaria is surrounded by an inner tissue layer called the gastrodermis. The outside of the organism has a tissue layer called the epidermis. Between these two tissue layers is a gel-like region called the mesoglea.