Taenia saginata - oncosphere Humans contract infective cysticerci by eating raw or undercooked meat. Once reaching the jejunum, the inverted scolex becomes evaginated to the exterior under stimuli from the digestive enzymes of the host. Using the scolex, it attaches to the intestinal wall. The larva mature into adults about 5 to 12 weeks later.
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It involves an unusual process in which two (endodyogeny) or more (endopolygeny) daughter cells are produced inside a mother cell, which is then consumed by the offspring prior to their separation. Also, budding (external or internal) occurs in some worms like Taenia or Echinococcus; these worms produce cysts and then produce (invaginated or evaginated) protoscolex with budding.
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Fruiting bodies, which grow in groups, are 1-3 mm in diameter, roughly spherical or ovoid in shape, and white to buff in color. The peridium (outer wall) consists of several layers, including a gelatinous layer. At maturity, the exoperidium (outermost layer) splits into several lobes to expose the dark brown, single peridiole (spore casing). The peridiole is forcibly ejected (sometimes up to several feet), leaving an evaginated endoperidium.
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In lizards and snakes, males possess paired hemipenes, each of which is usually grooved to allow sperm transport and spiny or rough at the tip to allow firm attachment to the female. To become erect, a hemipenis is evaginated (turned inside out) through muscle action and engorgement with blood. Only one is inserted into the female's cloaca at a time. In reptiles, the phallus has an open sulcus instead of a closed urethral tube.
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This greatly extended and evaginated, or protruding, part is what becomes the wing. By the close of the last instar, or fifth, the wing is pushed out of the wing-pocket, although continues to lie under the old larval cuticle while in its prepupal stage. It is not until the butterfly is in its pupal stage that the wing-bud becomes exposed, and shortly after eclosion, the wing begins to expand and form its definitive shape. The development of tracheation of the wings begin before the wing histoblast form, as it is important to note that they develop near a large trachea.
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The branchiostegal lung contains a tissue similar to that found in gills, but suited to the absorption of oxygen from air, rather than water. This organ is expanded laterally and is evaginated to increase the surface area; located in the cephalothorax, it is optimally placed to reduce both the blood/gas diffusion distance and the return distance of oxygenated blood to the pericardium. Coconut crabs use their hindmost, smallest pair of legs to clean these breathing organs and to moisten them with water. The organs require water to properly function, and the coconut crab provides this by stroking its wet legs over the spongy tissues nearby.
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As the tubule passes through the nozzle, it opens the operculum and uncoils after. Ballistics in cnidarians nematocysts is driven by synthesis of osmotic propellant poly gamma glutamate synthase, PgsAA, while in Polykrikos it is thought to occur due induced pressure as a result of capsular fibre contraction in the capsule wall. Nucleus is uniquely characterised by a double-layered fibrous cortex that underlines evaginated nuclear envelope; cortex is hypothesized to provide strength and shape to the nucleus, while nuclear evaginations are thought to increase nuclear-cytoplasmic exchange area at cortex perforation sites. In Polykrikos, well-defined fibrous ribbons are involved in nuclear-flagellar connections, and anchoring to flagellar apparatus might serve in orientation of the nucleus in relation to flagella during processes of movement, mitosis and cell division.
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