Digestive system of class asteroidea, Biology

Assignment Help:

Digestive System of Class Asteroidea

Most asteroids are scavengers or carnivores and feed on snails, bivalves, polychaets, other echinoderms, fish, sponges, sea anemones and polyps of hydroids and corals. Some feed on plankton and detritus. The digestive system of sea stars extends between the oral end and aboral disc of the animal. The mouth lies at the centre of a muscular peristomial membrane. The mouth is followed by a short oesophagus that in turn opens into a large stomach. The stomach occupies most of the interior of the disc and is divided by a horizontal constriction into a large oval cardiac stomach and a smaller, flattened pyloric stomach. The walls of gastric stomach are pouched. In each arm a pair of digestive glands or pyloric caeca are present and their ducts open into pyloric stomach. The pyloric stomach leads into a short tubular intestine on the aboral side. The intestine opens to the outside through a minute anus at the centre of the aboral surface of the disc. A number of small outpocketings called rectal caeca arise from the intestine.


Related Discussions:- Digestive system of class asteroidea

Explain prosthetic device infections, Explain Prosthetic device infections ...

Explain Prosthetic device infections Some infectious disease specialists recommend antimicrobial prophylaxis before process in patients with vascular grafts or orthopedic pros

Kingdom protista, what is the taxonomy of phylum sporoza?

what is the taxonomy of phylum sporoza?

Describe the organization of the vascular plant body, Describe the Organiza...

Describe the Organization of the Vascular Plant Body? A typical plant body consists of two distinct systems: a root system and a shoot system. The root system is usually below

Define energy needs during pregnancy period, Define Energy needs during pre...

Define Energy needs during pregnancy Period? Two factors determine energy requirements: increase in mother's basal metabolism to support the work required for foetal growth and

M - mode echocardiography, M-Mode was the earliest form of cardiac ultrasou...

M-Mode was the earliest form of cardiac ultrasound used clinically. It displays the amplitude signals of various structures along the length of ultrasound beam with distance or

Degradation of ecosystem, Degradation of Ecosystem Ancient man was si...

Degradation of Ecosystem Ancient man was simple-minded food gatherer and hunter. He looked upon nature with awe and respect and in fact he worshipped it. But from the time he

In what ways does poverty lead to environmental degradation, Question 1: ...

Question 1: (a) In what ways does poverty lead to environmental degradation? (b) What types of problems do the rural and urban poor share? Give some differences in the condi

RESPIRATION, I HAVE TO MAKE A ASSIGNMENT ON RESPIRATION

I HAVE TO MAKE A ASSIGNMENT ON RESPIRATION

What is the condition for mendels second law to be valid, What is the condi...

What is the condition for Mendel's second law to be valid? Mendel's second law is only valid for genes located in dissimilar chromosomes. For genes situated in the same chromos

Explain phosphofiuctokinase-i, Phosphofiuctokinase-I Phosphofiuctokina...

Phosphofiuctokinase-I Phosphofiuctokinase-I  is activated by AMP and  inhibited by ATP and citrate. When ATP is utilized in energy requiring process, the concentration ofAMP

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