Ptosis (droopy eyelid) may be inherited as a dominant human trait. Among 30 people who are heterozygous for the ptosis allele, 10 have ptosis and 20 have normal eyelids. What is the penetrance for ptosis?

#Question id: 4741

#SCPH01 Biochemistry

The F2 progeny from a particular cross exhibit a modified dihybrid ratio of 9 : 7 (instead of 9 : 3 : 3 : 1). What phenotypic ratio would be expected from a testcross of the F1?

#Question id: 4741

#SCPH06 I Botany

The F2 progeny from a particular cross exhibit a modified dihybrid ratio of 9 : 7 (instead of 9 : 3 : 3 : 1). What phenotypic ratio would be expected from a testcross of the F1?

#Question id: 4741

#SCPH12 I Genetics

The F2 progeny from a particular cross exhibit a modified dihybrid ratio of 9 : 7 (instead of 9 : 3 : 3 : 1). What phenotypic ratio would be expected from a testcross of the F1?

#Question id: 4741

#SCPH28 | Zoology

The F2 progeny from a particular cross exhibit a modified dihybrid ratio of 9 : 7 (instead of 9 : 3 : 3 : 1). What phenotypic ratio would be expected from a testcross of the F1?

#Question id: 4742

#SCPH01 Biochemistry

In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A recessive lethal allele that causes death of the embryo is sometimes present on the Z chromosome in pigeons. What would be the sex ratio in the offspring of a cross between a male that is heterozygous for the lethal allele and a normal female?

#Question id: 4742

#SCPH06 I Botany

In birds, sex is determined by a ZW chromosome scheme. Males are ZZ and females are ZW. A recessive lethal allele that causes death of the embryo is sometimes present on the Z chromosome in pigeons. What would be the sex ratio in the offspring of a cross between a male that is heterozygous for the lethal allele and a normal female?