Coxal glands, Biology

Coxal Glands

There is a pair of coxal glands, in almost all the segments in Onychophora (Peripatus). Developmentally; in every segment a hollow follicle or somite arises and in the trunk region, they become divided in dorsal and ventrolateral portions. The ventrolateral portion grows into the appendages and its cavity makes the end sac of the coxal gland. The end sac opens by a ciliated canal, the coelomostome, into acoiled excretory canal. The terminal portion of the canal is enlarged to form a vesicle or bladder. So the coxal glands are derived from coelomoducts. In arthropods there is a likeness in the formation of coxal glands from coelomoducts and the creation of gonads and their ducts.

In crustaceans they are found in third and sixth segments and they are suitably. named depending upon the site of their opening to outside. The one located at the base of the third segment opens at the base of the antenna, therefore called antennal gland. The one located in the sixth segment opens at the base of the second maxilla, and is termed as maxillary gland. Antennal gland is present in the larval forms of Ostracoda, Copepoda, Branchiopoda, Branchiura, Cirripedia and lower Malacostraca but TP the adults of these groups have maxillary glands. The adult amphipod and decapod crustaceans comprise antennal glands. Mysidacea, a primitive group of crustaceans have both of the antennal and maxillary glands functional. Most arachnids have a pair of coxal glands opening in the sixth segment, opening at the base of third pair of walking legs. In Limulus, there are four pairs of coxal glands.

Posted Date: 2/4/2013 4:27:30 AM | Location : United States







Related Discussions:- Coxal glands, Assignment Help, Ask Question on Coxal glands, Get Answer, Expert's Help, Coxal glands Discussions

Write discussion on Coxal glands
Your posts are moderated
Related Questions
harmful and beneficial usesa of phylum porifera

Structure and Content of Halsted Reitan battery Although there are several versions of the Halsted Reitan battery, the differences tend to be minor, and there appears to be a

Conventions for using binomial nomenclature The names of higher categories are often synthesized from Latin words in the same manner as generic or specific names, and always s

You are setting up a PCR reaction. a) The total volume of your reaction is 50 uL. Your stock primer solutions are 25 mM each. You want a final concentration of primer of 1 mM in yo

tell me the general characters of monopisthocotylea

Determine the biologic response The biologic response can include: i) Metabolic disturbance. ii) Inflammatory response iii) Immune response iv) Mutagenesis v) Ca

Epidemiology: This infection, although mostly occurring in cows, sometimes also occurs in buffaloes. Under natural conditions, the infection takes place through inoculation by the

Which are the phases of the menstrual cycle? The menstrual cycle is separated into two main phases: the follicular (or menstrual) phase and the luteal (or secretory) phase.

Genetics of Nitrogen-fixation The genetics of nitrogen-fixation is known in detail in Klebsiella pneumoniae. There are twenty genes required in organising the complete N 2 -fi

Which of the following is a true statement regarding the process of RNA editing? A. RNA editing alters the sequence of the mRNA message thereby permitting for an enhance in pro