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Allele definition biology || NEET | AIIMS ||

  Alleles  Each gene may exist in alternative forms known as alleles, which code for different versions of a particular inherited character.  We may also define alleles as genes occupying corresponding positions on homologous chromosomes and controlling the same characteristic (e.g. height of plant) but producing different effects (tall or short).  The term homologous refers to chromosomes that carry the same set of  genes in the same sequence, although they may not necessarily carry    identical alleles of each gene.             Wild-type Alleles Normal or Prevalent alleles in a population are called wild-type alleles. These alleles typically encode proteins that are made in the right amount and function normally.  Mutant Alleles   Alleles that are present at less than 1% in the population and have been altered by mutation are called mutant alleles ....
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Aristotle Lantern in Echinoderms

What Is Aristotle's Lantern? Our seas are filled with popular creatures – as well as those that are lesser known. This includes creatures and their unique body parts. One of them that has a unique body part and name are sea urchins. The term Aristotle's lantern refers to the mouth of sea urchins. Some people say, however, that it does not solely refer to the mouth alone, but the entire animal. Where Did the Name Aristotle's Lantern Come From? It's a funky name for a marine creature body part. This structure was named for Aristotle, a Greek philosopher, scientist and teacher who described the structure in his book  Historia Animalium,  or  The History of Animals.  In this book, he referred to the "mouth-apparatus" of the urchin as looking like a "horn lantern." Horn lanterns at the time were five-sided lanterns made up of panes of thin pieces of horn. Horn lantern The horn was thin enough for light to shine out, but strong...
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Water Vascular or Ambulacral System of Star Fish ; Asterias

how start fishes moves without fins??????  let see how ⇊⇊⇊ Water Vascular or Ambulacral System Water Vascular System is a unique feature of  of all the echinoderms which helps mainly in locomotion .  This it is the modified part of the coelom and consists of a system canals which is filled with sea water, containing amoeboid corpuscle s .   It plays a vital role in the· locomotion of the animal and obtaining food is the major function of water Vascular system.  The water vascular system of starfish consists of                 1. madreporite,                2. stone canal ,               3. ring canal,               4. radial canal,               5. Tiedemann’s bodies,               6....
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