Question

Complete the following punett square problems. Show punett square and all work for credit. 4. The lubber grasshopper is a very large grasshopper, and is black with red and yellow stripes. Assume that red stripes are expressed from the homozygous RR genotype, yellow stripes from the homozygous ir genotype, and both from the heterozygous genotype (Rr). What will be the phenotypic ratio of the offspring resulting from a cross of two grasshoppers, both with red and yellow stripes? 55. In humans, Duchene Muscular Dystrophy is a disorder that is sex-linked and carried on the X chromosome. The dominant allele D yields normal muscle movements, and the recessive allele d causes dystrophy. If a man with Duchene Muscular Dystrophy marries a woman who is homozygous dominant (XoXo) could any of their children of the disease? Could any of their children be carriers? What percents?

Answer 1

Ans1) CROSS-

Parents Rr X Rr

Gametes R, r R, r

GAMETES	R	r
R	RR	Rr
r	Rr	rr

Phenotypic ratio- RED : RED and YELLOW : YELLOW

1: 2: 1

Ans 2) CROSS-

Parents Father X Mother

XdX d   X XDXD

Gametes Xd    XD

Offsprings XDXd

None of the offspring is diseased.

All the offsprings are carrier. Hence 100% are carrier.