Sagarthakur_in

Tobacco mosaic virus (TMV) is a positive-sense single-stranded RNA virus species in the genus Tobamovirus that infects a wide range of plants, especially tobacco and other members of the family Solanaceae. The infection causes characteristic patterns, such as "mosaic"-like mottling and discoloration on the leaves (hence the name). TMV was the first virus to be discovered. Although it was known from the late 19th century that a non-bacterial infectious disease was damaging tobacco crops, it was not until 1930 that the infectious agent was determined to be a virus. It is the first pathogen identified as a virus. The virus was crystallised by W.M. Stanley. It has a similar size to the largest synthetic molecule, known as PG5.[1] Tobacco mosaic virus Transmission electron micrograph of TMV particles negative stained to enhance visibility at 160,000× magnification Transmission electron micrograph of TMV particles negative stained to enhance visibility at 160,000× magnification Vir

 Phylum- porifera  *  ( paros -  pore , ferre ~TO BEAR)      * Commonly called as " spongs ".     General characters  1 porifera  are all aquatic, mostly  marine few terrestrial .  2 The are. Sessile and sedentary & grow like plant.   3. BODY SHAPE : vase or cylinder like . 4 Symmetry:  Asymmetrical or radial.   5 The body surface  is perpforted .by numerous pores,  the ostia through which water  entous the body of one or more large opening .the oscula by which the water exist . 6 They consist of outer ectoderm & inner endoderm with an  intermediate layer of ,mesenchyme ; therefore diploblastic  7 mouth - absent , Digestion ~ intracellular  8  Excautory & respiration  organs are absent  9 contractile vacucles. Are present in some fresh water forms .  10 The sponges are monoecious .   Monoecious-‐》 present male and female reproductive system in (monoecious )  . 11  The nervous & sinsory cell are probably not differential.  12 Reproduction occurs by both sexual

 PROTOZOA.                                     (1st animal) NAMING 》》》 PROTOS : (FRIST) , ZOON :(ANIMAL)                      ORIGIN 》》pre - Cambrian                                      also known as frist animals.                      ``````````````````                            * General characters * 1 A cellular (not dived into cell ) . 2 the term PROTOZOA was called by goldfuss . 3 they simplist and most primitive  ANIMAL having level of oxg . 4 body consist of protoplast mass . 5 they are microscopic, primitive and eukaryotic.   6  habitats; aquatic/ freeliving/parasitic commensal . 7  Body : Asymmetric, Bilateral & radial.  8  Body naked/ covered by pellicle / shell / cyst . 9  Locomotion -- pseupodia ,  flagella , Cilla  sproxogaa.  10 nutrition- - holophytic ,holozoic, saprophytic) parasitic.  11  Digestion- - intracellular, food vocule . 12. Respiration-- diffusion--body surface.  13 Excretion. --  contractile  vacule (water balence )                                   14