FLORA WORLD

Formation of U rine The formation of urine involves three main steps like Glomerular filtration, Reabsorption and Secretion. These steps occur in different parts of nephron (functional unit of kidney). 1.      Glomerular filtration : The first step of urine formation is the blood filtration. It is carried out by the glomerulus, called Glomerular filtration or Ultra filtration . Kidney filtered about 1100-1200ml blood per minute. The glomerular capillary blood pressure causes blood filtration through layers. These are as follows a.      Endothelium of glomerular blood vessels b.      A basement memberane c.       The epithelium of   Bowman’s capsule The epithelial cells of   Bowman’s capsule called Podocytes are arranged in such a manner so that some minute spaces occurs between them called filtration slits or slit pores. In glomerular capillaries, high pressure is resp...

  Excretory Products and Their Elimination   Removal of nitrogenous waste like ammonia, urea, uric acid etc. along with excess of water and salt and pigment called Excretion or Removal of metabolic waste from body is called Excretion . These wastes are called excretory substances .   For elimination of these wastes animals have specialized organs are Excretory Organs . Depending upon the nature of excretory products, there are three mode of elimination of nitrogenous wastes from living body. These are as follows- A.    Amoinotelism B.    Ureotelism C.    Urecotelism   A.    Ammonotelism: The organisms which are found in water or have eccess amount of water, eleminates their nitrogenous wastes in the form of ammonia. Animals which reove their excretory waste in the form of ammonia, called ammonotelic animals. The process which they remove wastes from the body called, ammonotelism. Eg: Bony fishes, aquatic amphibians and aquatic...

  PLANT HORMONES (PYTOHORMONES)   Phytohormones are also known as Plant Growth Hormones or Growth Hormones or Plant Growth Regulators (PGRs). Phtytohormones are organic substances which are synthesiszed in minute quantities in one part of the plant body and transported to another part where they influence specific physiological process. Plant hormones control all the physiological and cellular activities like cell division, enlargement, flowering, seed formation, dormancy and abscission. A group of plant hormones including Auxins , Gibberellins , Cytokinins ,   Ethylene and Abscisic acid are presently known as growth regulators. Out of these Auxins , Gibberellins and Cytokinins have growth promoting effects , where as Ethylene and Abscisic acid (ABA) have growth inhibitory effects.     Basically PGR are divided into two main groups-   (A). Plant growth promoters- Auxins , Gibberellins and Cytokinins.   (B). Plant growth inhibit...