Already have an account? Get multiple benefits of using own account!
Login in your account..!
Remember me
Don't have an account? Create your account in less than a minutes,
Forgot password? how can I recover my password now!
Enter right registered email to receive password!
Metamorphosis in Amphibians
Metamorphosis is radical in anurans, slight or not exists in urodeles. In anuran amphibians like toads and most frogs, metamorphosis is generally associated with a transition from an aquatic to a terrestrial or amphibious mode of life. Occasionally though no transition in mode of life takes place as observed in the larval and adult of the frog Xenopus laevis and many primitive anurans that remain aquatic throughout their life. The change in habitat in the frogs and toads also generally results in a change in their feeding habit. In some like X laevis there is no change in food habit because both larvae and adult ale carnivorous. Some anurans go through an abbreviated type of metamorphosis before hatching, as they pass through a tailed, gilled tadpole-like stage within the jelly membrane of the egg. Others go through direct development by skipping the larval stages totally.
Metamorphosis in urodele amphibians is generally less striking. Some of them undergo direct development, while others fail to complete their metamorphosis. The latter acquire sexual maturity as larvae, as seen in the axolotl larvae of Ambystoma. This phenomenon is termed as neoteny. Some urodeles like salamanders have been observed to go through two metamorphosis. Metamorphosis in both anurans and urodeles essentially includes the activation of the genomic set underlying the adult organization, which needs for its expression a minimum mass of tissue i.e. greater than that of the egg. The activation is believed to be due to the secretion of a brain hormone that initiates metamorphosis. The hormone triggers the degeneration of redundant larval organs and growth of hitherto quiescent structures that are needed in the adult. In amphibians the process of destruction and growth are smoothly coordinated, as a result of which the animal retains its functional integrity throughout metamorphosis in place of lying dormant as in the case of insects.
Q. What is the organ where most of the clotting factors are produced? What is the role of vitamin K in the blood coagulation? Most of the clotting factors are produced in the l
Define effect of Caffeine on athletes? Caffeine is found in coffee, tea, colas and chocolates. Its doses at 3- 6 mg/d have been known to increase muscle contractility and aerob
Q. What is phosphorylation? What are various biological processes in which phosphorylation plays a critical role? Phosphorylation is the name given to procedure of the addition
What are the Pupillary defects There are certain deviations from normal pupillary reflexes which point towards certain specific pathology.
whats ur clear definition of virus
RECAPITUL A TIO N THEORY / BIOGENETIC LAW It was proposed by Muller & Haeckel on the basis of Baer's law. According to it, in the development of animal phylum characters
Q. What are the fundamental constituents of the cell membrane? The cell membrane is formed of lipids, carbohydrates and proteins. The membrane lipids are phospholipids, a sp
Q. In which kind of animals does the placenta exist? What is its major function? True placenta is present in placental mammals. The placenta is formed from the chorion of th
Define the Medical Complications of Bulimia Nervosa? The medical complications of bulimia nervosa range from fairly benign, transient symptoms, such as fatigue, bloating and co
Define the Wealth Care Delivery ? The challenge that exists today in many countries is to reach the whole population with adequate health case services and to ensure their util
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!
whatsapp: +91-977-207-8620
Phone: +91-977-207-8620
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd