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TLS Online TPP Program

#Question id: 6991

Metamorphosis of amphibians is triggered by environmental cues that act on the:

#Unit 5. Developmental Biology
  1. thyroid
  2. pituitary
  3. hypothalamus
  4. eye
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TLS Online TPP Program

#Question id: 29096

#Unit 8. Inheritance Biology

When a homozygous plant that produces purple fruit (PP) is crossed with a homozygous plant that produces white fruit (pp), all the heterozygous F1 (Pp) produce violet fruit If an F1 eggplant is used in a testcross, what proportion of the progeny from this cross will be white?
TLS Online TPP Program

#Question id: 29097

#Unit 8. Inheritance Biology

In the Palomino horses color is determined by three alleles at a single locus; C+/C+(light chestnut), C+/Ccr (Palomino), Ccr/Ccr (cremello). Chestnut is dominant over Palomino and cremello, and Palomino is dominant over cremello (C+/C+> C+/Ccr> Ccr/Ccr). What will be expected phenotypes and ratios of offspring produced by the C+C+/CcrCcr X C+Ccr/CcrCcr crosses?
TLS Online TPP Program

#Question id: 29098

#Unit 8. Inheritance Biology

A family in which club foot was inherited as an autosomal dominant trait. They discovered a mutation in the PITXI gene that caused club foot in this family. Through DNA testing, they determined that 11 people in the family carried the PITXI mutation, but only 8 of these people had club foot. Which of the following is the correct interpretation of the observation?
TLS Online TPP Program

#Question id: 29099

#Unit 8. Inheritance Biology

The type of plumage found in mallard ducks is determined by three alleles at a single locus: MR, which encodes restricted plumage; M, which encodes mallard plumage; and md, which encodes dusky plumage. The restricted phenotype is dominant over mallard and dusky; mallard is dominant over dusky (MR > M > md). The expected phenotypes and proportions of offspring is 3/4 restricted, 1/4 mallard by which of the following crosses?
TLS Online TPP Program

#Question id: 29100

#Unit 8. Inheritance Biology

The adult flies that emerged had a eyeless mutation phenotype in Drosophila produces greatly reduced eyes.. When this eyeless fly was crossed to a known reduced eye  mutant fly, all the progeny had normal phenotype. The observed phenotype can be best explained as an example of__
TLS Online TPP Program

#Question id: 29101

#Unit 8. Inheritance Biology

A cross between two yellow heterozygous mice produces an initial genotypic ratio of 1/4 YY, 1/2 Yy, and 1/4 yy, the F1 progeny showing lethality in their ratio, if F1 yellow heterozygous mate with nonyellow mice what will be the ratio in F2 generation?