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Different phenotypes and genotypes of one species
Corn Snakes Elaphe guttata
Pictures thanks to serpentine widget
Why do snakes look different when they are the same species ?
Corn snake color is comprised of two predominant colorsRedBlackYellow, appears in varying degrees and is not
the main reason for pattern changePhenotypes of corn snakes include
Normal –red and black occur togetherAmelanistic – only redAnerythristic- only blackSnow- neither
Genotype and PhenotypeTwo genes that code for color
Gene for black color on the ventral surface (belly) and around the saddle patterns
Gene for red color in the pattern of the saddles and the back ground on the snake
Wild type allele B- black pigmentRecessive b- can no longer make black pigment-
amelanisticWild type allele R- red pigment
Recessive r- can no longer make red pigment- anerythristic
Double recessive- Snow Corn Snake (rrbb)
Cross each one of Mr. Reed’s SnakesMr. Reed has these snakes
amelanistic corn snake (RRbb or Rrbb),
a normal corn snake (RRBB or RrBb),
a snow corn snake (rrbb)
Could Mr. Reed breed his snakes to make an Anerythristic snake (no red pigment)?
What is the genotype for the Anerythristic snake?
Which parental genotypes could you cross to create an Anerythristic snake? List all possible crosses.