Search results
Results from the WOW.Com Content Network
The coxal gland is thought to be homologous with the antennal gland of crustaceans. The gland consists of an end sac (saccule), a long duct (labyrinth) and a terminal bladder (reservoir). [2] There is generally only one pair (two in some spiders), and they open on the coxae of the walking legs [1] or at the base of the second antennae in the ...
In Crustacea, the saccate metanephridia are associated with the antennae and form the antennal gland. In freshwater crustacea , the saccate metanephridia are especially large due to their role in osmoregulation; crustacea must remove large amounts of water from the tissues, as the cells are hypertonic to the surrounding water.
Opioid peptides and opioid receptors occur naturally in crustaceans, and although it was concluded in 2005 "at present no certain conclusion can be drawn", [3] more recent considerations suggest their presence along with related physiological and behavioural responses as indicating that crustaceans may experience pain.
A tripartite structure is recorded from near the antennae, consisting of elevated walls arranged in a semicircle (likely to enlarge the surface for an excretory organ as in modern crustaceans), a pore representing an opening of the “antennal gland” (the purpose of which is unknown) and a sickle-shaped furrow surrounding this pore.
However, careful control is required because physiological changes can occur due to noxious, but non-pain related events, e.g. cardiac and respiratory activity in crustaceans is highly sensitive and responds to changes in water level, various chemicals and activity during aggressive encounters.
Lymph nodes may become enlarged in malignant disease. This cervical lymphadenopathy may be reactive or metastatic. [1] Alternatively, enlarged lymph nodes may represent a primary malignancy of the lymphatic system itself, such as lymphoma (both Hodgkin's and non-Hodgkin's), [6] lymphocytic leukemia, [1] Lymphadenopathy that lasts less than two weeks or more than one year with no progressive ...
An ionocyte (formerly called a chloride cell) is a mitochondrion-rich cell within ionoregulatory organs of animals, such as teleost fish gill, insect Malpighian tubules, crustacean gills, antennal glands and maxillary glands, and copepod Crusalis organs. [1]
The most usual signs and symptoms are the appearance of a chronic, painless mass in the neck, which is persistent and usually grows with time. The mass is referred to as a "cold abscess", because there is no accompanying local color or warmth and the overlying skin acquires a violaceous (bluish-purple) color.