Lens regeneration in amphibians, Biology

Lens Regeneration in Amphibians

It is an amazing fact that between all vertebrates only certain amphibians have the unique ability to regenerate lens, iris and retina in adult lire. The amphibians also change in their capability to regenerate a lens and in the source of cells from which a new lens is formed. Members of sub-order salamandridae (salamander, Triturus) have the significant ability of growing a new lens from the dorsal iris epithelium (neural ectoderm).

This is a unique instance of metaplasia, as the regenerating iris is derived from neural ectoderm and may be regarded as an extension of the brain whereas the original lens is derived from the epidermal ectoderm. This kind of regeneration has demonstrated that even adult differentiated cells can keep their potential to produce other cell types. In the larvae of the South African frog. Xenopus laevis an invagination of corneal epithelium gives increment to a ball of cells which transforms into the new lens. The procedure of the new lens regeneration in X. laevis more closely duplicates the embryonic process, like both the first lens and the regenerate lens develop from cells of epidermal ectodermal origin, though, even so it is a case of metaplasia, since differentiated cells of corneal epithelium give rise to lens cells that are morphologically and biochemically very different from those of the corneal epithelium. The regenerating capability in this anuran however species disappears at metamorphosis.

Posted Date: 1/31/2013 4:53:52 AM | Location : United States







Related Discussions:- Lens regeneration in amphibians, Assignment Help, Ask Question on Lens regeneration in amphibians, Get Answer, Expert's Help, Lens regeneration in amphibians Discussions

Write discussion on Lens regeneration in amphibians
Your posts are moderated
Related Questions
Explain the Recommended Dietary Allowance for nicotinic acid? There are various factors and which niacin requirements depend. These are energy Utilization, body size and dietar

The DNA replication is a biological procedure which happens in all living organisms and copies their DNA; it is the basis for biological inheritance. The process will starts when o

Which one of the following structures between two adjacent cells is an effective transport pathway? 1. Plasmodesmata 2. Plastoquinones 3. Endoplasmic reticulum 4. Plasm

Q. Do all molecules of DNA have the same amounts of nitrogenous bases? Number and sequence of nitrogenous bases in DNA molecule are key elements in variations which are found i

Thermodynamics and Cell Shapes Why are protoplasts (cells devoid of cell wall) spherical? Why are most of the unicellular organisms (prokaryotes and eukaryotes) spherical? A s

Foraminiferans - Protozoan Foraminiferans are largely benthic marine species. They have multi chambered calcareous tests or shells with numerous pores, hence the name foramini

Enumerate the different means of evaluating the implant prior to stage 2 surgery. The Different means for evaluating the implant prior to stage 2; i) Radiographic evaluation

M protein of rheumatogenic GAS has distinct structural characteristics that are akin to human heart tissue, particularly sarcolemmal membrane proteins and cardiac myosin. The major

Thermal Stratification - Lake Ecosystem Shallow lakes show no thermal stratification as their waters are well mixed, resulting in uniform temperature throughout. However lakes

Q. Nature of disease? Education is very important for diabetics because it is a lifelong disorder. In order to enable the patient to lead a healthy and a good quality Life free