Azoospermia is the medical condition of a man whose semen contains no sperm. It is associated with infertility, but many forms are amenable to medical treatment. In humans, azoospermia affects about 1% of the male population and may be seen in up to 20% of male infertility situations. 1 Classification 1.1 Pretesticular.
Nematocysts are the stinging cells on tentacles of a cnidarian, like a jellyfish. Since jellyfish don't have any teeth, and their body consists of gelatin, it's hard to captur â¦ e prey.Nematocysts help jellyfish with feeding by stinging the prey in an attempt at trying to immobilizing the prey.hat is a Cnidarian? cnidarians, such as jelly fish, sea anemones, hydra, and corals, have tentacles surrounding their mouth. they are a hollow-bodied animal with two celled layers that are organ â¦ ized into tissues. the inner layer forms a digestive cavity where food is broken down.
In some species, cnidocytes can also be used as anchors. Like sponges and ctenophores, cnidarians have two main layers of cells that sandwich a middle layer of jelly-like material, which is called the mesoglea in cnidarians; more complex animals have three main cell layers and no intermediate jelly-like layer.any have complex lifecycles with asexual polyp stages and sexual medusae, but some omit either the polyp or the medusa stage. Cnidarians were for a long time grouped with Ctenophores in the phylum Coelenterata, but increasing awareness of their differences caused them to be placed in separate phyla.