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Phenotype Dominant Alleles Recessive Alleles Ear size (li+le or big) Big ears (B) Li+le ears (b) Tail (long or short) Short (S) Long (s) Spots or no spots No spots (P) Spots (p) Color Black (H) Not black (h) *linked on same chromosome Let’s choose “Rascal”! Rascal’s genotype is: Bb, ss, pp, Hh Note: the genes for spots and hair color are linked (occur on the same chromosome). 1.  What is Rascal’s phenotype? Rascal has: big ears, a long tail, spots, and black hair. 1.  Draw Rascal’s cell at: a) 
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G1 G2 metaphase of meiosis 1 products of meiosis 1 metaphase of meiosis 2 products of meiosis 2 (gametes) 2.  Use a Punne+ Square to predict the outcomes of a cross between Rascal and Emma. Emma is homozygous recessive for all loci. What are the raUos of genotypes and phenotypes for Rascal and Emma’s puppies? KEY 2a. Cell at G1 p b H s B p h s KEY 2b. Cell at G2 p p H H b b s p h s B p h s s B KEY 2c. Cell at Metaphase of Meiosis 1 s s s s p p p p H H h h b b B B KEY 2d. Products of Meiosis 1 s s p p H H s b p p h h s b B B KEY 2e. Metaphase of Meiosis 2 s s s s p p p p H H h h b b B B KEY 2f. Products of Meiosis 2 s s b B p p h H s s p b B H p h KEY What gametes are possible for each parent? Genotype Father (Rascal) Mother Bb ss pp Hh Genotypes B s p H of gametes B s p h b s p H b s p h bb ss pp hh b s p h PunneI Square: b s p h B s p H Bb ss pp Hh B s p h Bb ss pp hh b s p H bb ss pp Hh b s p h bb ss pp hh All puppies will have long tails and spots (ss, pp). 25% will be black w/big ears (Bb, Hh) 25% will be black w/liIle ears (Bb, hh) 25% will be not black w/big ears (bb, Hh) 25% will be not black w/liIle ears (bb, hh)