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NPC system of Classification | Pollen and spore aperture | Bsc exam purpose

NPC SYSTEM OF CLASSIFICATION NPC is an artificial system of classification of pollen and spores based on the three features of aperture only,i.e. number,position and character. ************************************* 2 famous botanists Erdtman and Straka in 1961 proposed NPC classification and people all over the world have accepted it.So according to this system each pollen grain has an arithmetic cardinal number consisting of 3 digits.The first digit reveals the presence and absence of aperture and if present it tells about the total no.of apertures present in them.The 2nd digit reveals the position of aperture. and the 3rd explains the character of an aperture.So the name NPC, meaning n for number,p for position and c for character.Now let us study one by one.The first one is Number i.e. classification based on number--- N denotes the number.Mainly pollen having aperture is divided into 7 groups mentioned as N1 to N7. N1 has one aperture,N2 has 2 and so on.....Each of these are named as N1-monotreme,N2-ditreme,N3-tritreme,tetratreme,pentatreme,hexatreme, and polytreme for N7. Further there are some pollen grains where apertures are absent and thsea come under N0 group. there is another special group N8-named anomotreme where pollen grain have one to many irregularly spaced apertures. So thats all about classification of pollen grains on number. ******************* Lets move on to the next one i.e. classifiction based on position Here P represents the position of aperture.There are 7 groups in this. starting from P0 to P6.P0 have uncertain or unknown position of aperture. P1 is called catatreme-that means these have only 1 aperture that too at the proximal end of the grain. P2 is called anacatatreme-meaning these have 2 apertures one at the proximal end and other at the distal end. P3 is called anatreme-only one aperture that at the diatsal position P4 is called zonotreme-having apertures on equator or sub equator. P5 is called dizonotreme-apertures arranged in 2 or more zones P6 is called pantotreme-here apertures are scattered all over the place. ********************** So now remains the last one that is classification based on character denoted by C.There are 7 groups from C0 to C6. C0 is group of apertures whose characters cant be defined C1 is called monlept-because they have one leptome.Leptoma may occur on either proximal or distal face and termed accordingly as catalept and analept. C2 is called trichotomocolpate-3 branched apertures amd branches are more than 2 times longer than breadth. C3 has colpate grain C4 has porate grain C5 has colporate C6 is called pororate pollen.Because they have porous pollen. I am not the owner of any content which I used in my video.All resource like picture or video from Google or any other helpful site which help us to video making so I credit to my all work to Google or any other site if I used any other's content then I will definitely credit to him thanks, I hope all owners understand to me if I used some content in my video thanks again all owners. Like, comment, share and subscribe!