KINGDOM-MONERA

on
MONERA-PROKARYOTES
Bacteria are the sole member of Monera Kingdom.


(1) Cell wall:-
Cell Wall of prokaryotes is made up of peptidoglycan (or murein) which is a type of mucopeptide.

(2) Cell membrane:-
(A) Like eukaryotes the cell membrane of prokaryotes is made up of lipoprotein [liquid + protein]
(B) The space between cell wall and cell membrane is known as periplasmin space. This space, is analogous (functionally same)to lysosome because in this space the digestion of complex substance is done.

(3) Cytoplasm:-
(A) The cytoplasm of prokaryotes lack membrane bound cell organelles.
(B) In prokaryotic cell, the nucleus is indistinct. The nucleus of  prokaryotes is also known as  incipient, nucleus, genophore, nucleoid or fibrillar nucleus. Nucleus membrane is absent around nucleus. It also lack nucleolus.

Prokaryote also back the true chromosome.Instead of it,a false chromosome is present which is made up of ds circular naked DNA+Non histone protein like polyamines.This false chromosome coils and form chromosomal regio which is known as nucleoid
(C) In prokaryote ribosomes are of 70s type.Ribosome are the sites of protein synthesis.
                        
                                                                SHAPE
Bacteria have variations in their shape. On the basis of their shap bacteria are of different types.

(1) coccus

  • These Bacteria are spherical 
  • These are smallest bacteria 
  • Maximum resistant bacteria 

(2) Bacillus:-

  • This group includes most of the bacteria 
  • There are rod shaped e.g. Escherechia coli.

(3) Spirillum:-

  • These are spiral shaped bacteria 
e.g. Spirillum volutans, Treponema


(4) Comma (Vibrio) :-
  • These are comma shaped bacteria 
e.g. Vibrio cholerae




STRUCTURE OF FLAGELLUM
A flagellum of bacteria is made up of three parts
(1)Basal body       (2)Hook                (3)Filament
I)Basal body:-
a)      It is the basal of flagellum and rod shaped in structure.
b)      It lies with cell wall and cell membrane
c)      This proteinaceous rod shaped structure is surrounded by two pair of ring
(i)                 Outer pair                  (ii)  Inner pair
d)      Outer pair of ring lies with in the cell wall. One ring of this pair is called L and another called P.
e)      Inner ring of inner pair lies with in the membrane. One ring of this pair is called S and the another is called M.
f)       In Gram (+) bacteria only pair of rings (inner pair) is found

II)Hook:-
a) It connect the basal body to filament 
b) It is the middle part of flagellum

III)Filament:-
a) It is cylindrical hallow structure made up of protein monomers.
b) Each monomer is made up of Flagellin protein. Monomess are arranged in spiral manner. Flagellin is a contractile protein..
      PILI                                    

 a) Bacteria cell wall is covered by numerous hair like structures call pili. Pili are smaller than flagella.
(sing. - pilus)
 b) They are of two types
 A.Longer pili                  B.Shorter pili.
c)Longer pili are known as 'F' pili and 'sex' pili. Longer pili occur in only donor (F﹢ or male) bacteria and help in conjugation. These are absent in recipient bacteria or female
d) The shorter pili take part in attachment. These are also known as 'infective' pili or fembriae. These are found in only in pathhhogenic bacteria.
   

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