scholarly journals THE DORSAL PYGIDIAL GLANDS OF THE FEMALE COCKROACH, BLATTELLA GERMANICA

1918 ◽  
Vol 50 (8) ◽  
pp. 278-280 ◽  
Author(s):  
E. H. Dusham
Keyword(s):  
Blattella Germanica ◽  
Pygidial Glands ◽  
Cockroach Blattella Germanica

Origin and Extent of Resistance to Fipronil in the German Cockroach, Blattella germanica (L.) (Dictyoptera: Blattellidae)

2003 ◽  
Vol 96 (5) ◽  
pp. 1548-1558 ◽  
Author(s):  
Glenn L. Holbrook ◽  
Jamie Roebuck ◽  
Clyde B. Moore ◽  
Michael G. Waldvogel ◽  
Coby Schal
Keyword(s):  
Blattella Germanica ◽  
German Cockroach ◽  
Cockroach Blattella Germanica

scholarly journals Absence of rDNA amplification in the uninucleolate oocyte of the cockroach Blattella germanica (Oorthoptera: Blattidae).

1976 ◽  
Vol 71 (1) ◽  
pp. 49-58 ◽  
Author(s):  
M D Cave
Keyword(s):  
Ribosomal Rna ◽  
General Pattern ◽  
Blattella Germanica ◽  
Nucleolar Organizer ◽  
Extrachromosomal Dna ◽  
Total Dna ◽  
Cockroach Blattella Germanica ◽  
Rdna Amplification ◽  
Large Nucleolus

Amplification of the genes coding for ribosomal RNA oocurs in the oocytes of a wide variety of organisms. In oocytes of various species of crickets (Orthoptera: Gryllidae) the amplified DNA is contained in a large extrachromosomal DNA body. Multiple nucleoli form about the periphery of the DNA body during the diplotene stage of meiosis I. In contrast to the general pattern of orthopteran oocytes, oocytes of the cockroach Blattella germanica demonstrate a single large nucleolus instead of many nucleoli. In order to determine whether the genes coding for rRNA are amplified in the oocytes of B. germanica, the relative amount of rDNA in oocytes was compared with the rDNA content of spermatocytes and somatic cells. An extrachromosomal DNA body similar to that present in crickets is not present in B. germanica. A satellite DNA band which contains nucleotide sequences complementary to rRNA accounts for approximately 3-5% of the total DNA in somatic and in male and female gametogenic tissues. Female cells contain approximately twice as much rDNA as do male cells. An XX-XO sex-determining mechanism is operative in B. germanica. In situ hybridization with rRNA indicates that the nucleolar organizer is located on one end of the X chromosome and that oocytes do not contain more than twice the amount of rDNA found in spermato cytes. The data indicate that rDNA is not amplified in the uninucleolate oocyte of B germanica.

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