Coxal glands, Biology

Assignment Help:

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.


Related Discussions:- Coxal glands

Management and nutritional intervention using mna, Define Management and Nu...

Define Management and Nutritional Intervention using MNA - Undernutrition? A. For those categorized as well-nourished They need only be reminded of the importance

Phototropic curvature is the result of uneven distribution, Phototropic cur...

Phototropic curvature is the result of uneven distribution of : 1. Gibberellin 2. Phytochrome 3. Cytokinins 4. Auxin Auxin

Types of cleavage, TYPES OF CLEAVAGE - Depending upon the distribution ...

TYPES OF CLEAVAGE - Depending upon the distribution & amount of yolk, cleavage is of following types - 1 .      HOLOBLASTIC EQUAL CLEAVAGE ( holos , whole ; blastos, ger

Which foods are used by microorganisms for energy, Q. Which Foods are used ...

Q. Which Foods are used by Microorganisms for Energy? The carbohydrates, especially the sugars, are most commonly used as an energy source, but other carbon compounds can also

Complete test of hypothesis, Conduct a test of hypothesis to verify whether...

Conduct a test of hypothesis to verify whether a difference exists among the average numbers of ant species found at sites in the two regions of Mongolia. Use  .  You will require

Which part of body is the main site of gluconeogenesis, Gluconeogenesis syn...

Gluconeogenesis synthesizes glucose from noncarbohydrate precursors, involving pyruvate and lactate, citric acid cycle intermediates, the carbon skeletons of most glycerol and amin

Water loss during excretion, Water loss during excretion In terrestria...

Water loss during excretion In terrestrial animals body water is also lost during excretion of nitrogenous wastes. A number of physiological adaptations have taken place to mi

Anatomy and Physiology, I have a test online it is timed 30 minutes on Anat...

I have a test online it is timed 30 minutes on Anatomy and Physiology I need an expert who is an expert in this subject to take it for me

Under which form is nitrogen fixed by living beings, Under which form is ni...

Under which form is nitrogen fixed by living beings? Most living beings cannot use molecular nitrogen to get nitrogen atoms. Producers fix nitrogen mostly from nitrate (NO3-).

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd