Fragmentation - types of asexual reproduction, Biology

Fragmentation - Types of Asexual Reproduction

Fragmentation is a phenomenon where parent animal spontaneously (on its own accord) splits into two or more fragments. Each one of such fragments after that regenerates the missing parts to form a new individual. This method is reported in specific sea- anemones and some worms. Sea anemones occasionally break off part or whole of their pedal disc whereas the main body moves away (pedal laceration). The pedal disc may put out lobes that pinch off and regenerate into small sea anemones. Occasionally a sea anemone leaves behind its pedal disc along with a few mesenteries at the site of attachment, in such types of cases the part left behind regenerates into a new sea anemone and the another main part regenerates the missing pedal disc. Fragmentation may be considered like a type of fission. Moreover longitudinal and transverse fission takes place as a normal method of asexual reproduction in many sea anemones. Spontaneous separation is beautifully demonstrated in certain freshwater planarians (Platyhelminthes, Class Turbellaria). A general example is Dugesia. The fission takes place when the animal has grown to the maximum size. The fission plane usually forms behind the pharynx.

At that time the hind part of the animal is firmly attached to the substratum and the front part continues to move forward until the worm breaks at the constriction into an anterior and a posterior segment. Each segment next regenerates the missing parts to form a new small worm. In some planarians like Microstomum, chains of individuals may be formed as a result of repeated fission. When these individuals develop and acquire a certain degree of differentiation, they separate from the chain.

Posted Date: 2/5/2013 12:11:57 AM | Location : United States







Related Discussions:- Fragmentation - types of asexual reproduction, Assignment Help, Ask Question on Fragmentation - types of asexual reproduction, Get Answer, Expert's Help, Fragmentation - types of asexual reproduction Discussions

Write discussion on Fragmentation - types of asexual reproduction
Your posts are moderated
Related Questions
Define Nutritional Requirements of Fats and Oils during Infancy? Adequate breast-feeding ensures 30 g fat intake by infants, of which 10% is linoleic acid and 1% is linolenic a

Future - Development Biology Fertilization in flowering plants is essential for sustaining life on earth. Production of most crops depends on the effectivity of the fertilisat

Carbohydrate - contains Carbon , Hydrogen , and Oxygen with a general formula of C x (H 2 O) y Simple sugars à monosaccharides Oligosaccharide à sugars containing

Determine the term -Stolon. In a number of colonial cnidarians, ascidians, and lophophorans, a cord of tissue connects different zooids of colony to each other. Buds on stolon

Apomictic embryos in citrus arise from: 1. Synergids 2. Maternal sporophytic tissue in ovule 3. Antipodal cells 4. Diploid egg Maternal sporophytic tissue in ovule

what major nerve do you think is being compressed when a person often feel pain in the posterior surface of the thigh radiating to the area behind the knee and where is the likely

Q. Can you briefly explain about parasitism? The Parasitism is an inharmonious interspecific ecological interaction in which individuals of a species (the parasites) explore or

Q. What are the cell movements and how are these movements created? Cell movements are movements executed by cell structures, like the movements of flagella and cilia, the pseu

Approximate Composition of Human Tissue Table gives the approximate composition of human tissue. We all know that carbon, oxygen, hydrogen are present in water and other organ

What is End-to-End Anastomosis with Subclavian Flap Aortoplasty ? The two operations can be combined as a single procedure. Medially end-to-end anastomosis is done between the