Which is the best looking?

Thursday, August 8, 2013

Sandboasomes

Heres a little reproduction background. Females gametes aka eggs are haploids, meaning they only have 23 chromosomes. All of these have 22 autosomes which determine which genes are inherited and one X. Now gametes are not like normal cells, most cells contain 46 chromosomes, a pair of the 23. We all know that when the sperm reaches the egg a zygote is formed a baby grows and pops out after 9 months blah blah blah. In humans the way sex is determined is 100% dependent on the males. The sperm either have a Y chromosome or an X chromosome, its 50/50. If a sperm with the Y reaches the egg a boy develops, if X, a girl. The combination of both 23 (haploids) create the full 46 (diploid) I'm not sure how sex is determined in sand boas, but based on a 1970 study of boid karyotypes (chromosome pictures) it was determined that the kenyan sand boas close relative, the javelin sand boa has 34 total chromosomes but they are not arranged the same as humans. They have 16 macrochromosomes and 18 microchromosomes. To be perfectly honest i do not know what the significance of this is, but it does not appear to mention any of these chromosomes determining sex, though I'm sure they do. Sand boas karyotype is unique among boas as they have two less than the usual amount of micro chromosomes, and their macrochromosomes include 8 metacentric and 8 acrocentric chromosomes, as opposed to the usual 10 and 6. Metacentric chromosomes have the typical X shape with the four armish things, where as acrocentric chromosomes are more of a half X. If thats confusing there's a picture below.

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