Topic: Mendel\'s Principles and Meiosis 1. Mice can differ in coat color (black
ID: 187122 • Letter: T
Question
Topic: Mendel's Principles and Meiosis 1. Mice can differ in coat color (black or brown) and nose twitchiness (twitchy or non- twitchy [chil]). The following matings were done, giving the indicated progeny: mating 2 mating 1 brown twitchy x brown twitchy brown twitchy x brown non-twitchy offspring included the phenotypes below (not necessarily in equal proportions): black twitchy brown twitchy black non-twitchy brown non-twitchy black twitchy brown twitchy black non-twitchy brown non-twitchy (a) which are the dominant phenotypes? how can you tell? (b) What are the parental genotypes in each of the two matings? Assuming independent assortment, what are the expected proportions of the progeny phenotypes in each of the two matings?Explanation / Answer
Answer:
Based on the given data:
Mating 1:
Brown Twichy (BbTt) x Brown Twitchy (BbTt)
Punnett Square
Phenotype:
Phenotype Ratio:
Phenotypic Ratio: 9:3:3:1
Mating 2:
Brown Twitchy (BbTt) x Brown Non-Twitchy (Bbtt)
Punnett Square:
Phenotype:
Phenotype Ratio:
Phenotype Ratio: 3:3:1:1
BT Bt bT bt BT BBTT BBTt BbTT BbTt Bt BBTt BBtt BbTt Bbtt bT BbTT BbTt bbTT bbTt bt BbTt Bbtt bbTt bbtt