A Pea plant that is homozygous for inflated pods are heterozygous for round seeds is crossed with a plant that is heterozygous for inflated pods and a homozygous for wrinkled seeds this across would produce a 4:12 or 1:3 phenotypic ratio true or false

Respuesta :

The answer is False!

P - dominant allele for inflated pods
p - recessive allele for inflated pods
PP - homozygote with inflated pods
Pp - heterozygote with inflated pods
pp - homozygote with inflated pods

S - dominant allele for round seeds
s - recessive allele for wrinkled seeds
SS - homozygote with round seeds
Ss - heterozygote with round seeds
ss - homozygote with wrinkled seeds

1. A Pea plant that is homozygous for inflated pods are heterozygous for round seeds: PPSs
2. A
 plant that is heterozygous for inflated pods and a homozygous for wrinkled seeds: Ppss

Let's look at their genotypes separately, and cross them that way:

Parents:              PP       x      Pp
Offspring:     PP      PP      Pp     Pp
All of the offspring will have the same phenotype (100% = 1). So, this trait does not affect phenotypic ratio

Parents:              Ss       x      ss
Offspring:     Ss      Ss      ss     ss
Half of the offspring will have wrinkled seeds and half of them will have round seeds: 50% : 50% = 1 : 1

So, the phenotypic ratio is not  1 : 3