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.
Define crucial periods of a woman's life - pregnancy and lactation? In this unit, we studied about the most crucial periods of a woman's life, pregnancy and lactation, especial
Q. False Positive ST Changes? 1) The slope of the PQ-segment can help predict the magnitude of the influence of P-wave depolarization and thus help predict which patient wou
LIVE R (HEPAR) - Largest gland of body. Weighing 1.6 kg. Form 1/40 of the body weight. Bio-chemical laboratory. Bussiest part in whole river of life. Dark reddish brown
PROTOPLAST Cell without cell membrane (Henstein) It contains 1 or more vacuoles. In mature plant cells protoplast forms a peripheral layer called Primordial utricle.
Entry of Pollen Tube into the Embryo Sac The pollen tube enters the embryo sac through the filiform apparatus of ong of the synergids. Generally, one of the synergids degenera
Normal 0 false false false EN-IN X-NONE X-NONE MicrosoftInternetExplorer4
Percussion - criteria for endosteal implants? It is neither an indicator of clinical health nor of rigid fixation. Ringing sound that occurs on percussion corresponds to the pr
1- Describe the function of enzymes in catalyzing biological reactions ? 2-Descride enzymes ' role in reducign activation energy?
Feeding management Feeding management deals about the in-house management in which the feed consumption pattern is well understood in the sheds and suitable alterations are made
On a given microscope, the numerical aperture of the objective is 1.5. The microscope is provided with a filter that selects a wavelength of 500 nm. What is the limit of resolution
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: +1-415-670-9521
Phone: +1-415-670-9521
Email: [email protected]
All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd