When happened forge of spermatozoa with core of egg, happened also association of material coming from two source. Whether egg and or spermatozoa bring the nature of from each mains that is chromosome. Chromosome represent small object, located in core of cell, accountable for evacuation or
transmission of[is nature of clan. This chromosome can only seen when happened bisection of cell by mitosis especially at the (time) of metaphase by special coloration. Size measure and that chromosome form differ in different fish species. But that chromosome can be differentiated to become 4 kinds of as follows ( Draw 16 ):
a = Acro(Telo)Centric ( t). chromosome of Telocentric its its[his] that is place area patch yarn when located mitosis near by one of [the] tip of chromosome.
b = Subtelocentric ( st). chromosome of Subtelocentric its [of] nearby him to tip of chromosome, but there are short chromosome arm.
c = Submetacentric ( sm). chromosome of Submetacentric its its[his] located in midst. chromosome. Both [of] its chromosome arm seen unegual but length.
d = Metacentric ( m). chromosome of Metacentric its its[his] with two chromosome arm which [is] of uniform length in the centre of.
Picture 16. Kinds of fish chromosome form ( Kirpichnikov 1981).
According to other writer [of] chromosome of telocentric [is] chromosome which don't have [both/ second] chromosome arm after terminal of centromer, at variance with chromosome which [is] acrocentric have short chromosome arm. Chromosome classification become 4 that form pursuant to comparison of chromosome arm length.
[Do] not all fish have that chromosome form seen together when metaphase. There [is] fish which only having chromosome of acrocentric and of subtelocentric, or in other species only consisting of chromosome of metacentric sub or of metecentric. Very often [at] fish got 2 or 3 kinds of chromosome, despite of also having its it[him] form chromosome. [At] a number of fish of teleost, and so do [at] fish of cucut ray and and also in Acipencerridae and of Amiidae, in its chromosome [is] got " micro-chromosome" which its for small but very quantitative difficult. There [is] also fish having chromosome with its satellite like [at] fish of Salmonidae with form like [at] Picture 17.
Picture 17. Fish chromosome with satellite
Can be paid attention that every pregnant chromosome two form which [is] identik and parallel which named [by] kromatid. Every kromatid consist of one or some flimsy filament which named [by] or kromonemata of genonemata. [At] this kronemata there are one absorbent area [of] more coloration and this area [is] named [by] kromomer. Kromonema represent long double filament, its for diametrical if that cell [is] spliting and if that cell [is] taking a rest or interphase its for tress like spiral. In cell which [is] taking a rest that way that flimsy and long kromonemata fill the core of cell form network which [is] komplek, difficult but seen below/under microscope, only one or two seen nukleoli.
Source : M. Ichsan Effendie, 1997
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