What traditional christmas decoration is actually a parasitic plant?

Two diallelic unlinked genes
Gene E controls eye shape: Dominant allele E expresses square eyes, and recessive allele e expresses round eyes.
Gene T controls the tail size. Dominant allele T expresses long trail, and recessive allele t expresses short tail.

Genotypes Phenotypes

EETT, EeTT, EETt, EeTt Square eyes and Long tail

eeTT, eeTt Round eyes and Long tail

EEtt, Eett Square eyes and Short tail

eett Rounf eyes and short tail.

1. An individual of this new species is heterozygous for gene E and heterozygous for gene T. What is their genotype and phenotype?

The heterozygous individual is E/e ; T/t, expressing square eyes and a long tail.

2. Two individuals, who are both heterozygous for eye shape and tail size, mate. Which of the following is a correct statement about the phenotype ratios expected for their offspring?

Cross: between two heterozygous individuals

Parentals) EeTt x EeTt

Gametes) ET, Et, eT, et

ET, Et, eT, et

Punnett square) . ET Et eT et

ET EETT EETt EeTT EeTt

Et EETt EEtt EeTt Eett

eT EeTT EeTt eeTT eeTt

et EeTt Eett eeTt eett

F1) Genotype:

1/16 EETT
2/16 EETt
1/16 EEtt
2/16 EeTT
4/16 EeTt ⇒ 1/4 EeTt
2/16 Eett
1/16 eeTT
2/16 eeTt
1/16 eett

Phenotype

9/16 E-T-, Square eyes and Long tails
3/16 E-tt, Square eyes and short tails
3/16 eeT-, Round eyes and Long tails
1/16 eett, round eyes and short tail

Phenotypic ratio 9:3:3:1

3. From the mating described in question ABOVE, what proportion of ALL of the offspring in will be heterozygous for both traits?

4/16 = 1/4 = 25% of the progeny are expected to be heterozygous for both traits, EeTt.

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3 years ago