Genetics Answers

4. An agricultural geneticist who uses
Nepenthes distillatoria (the carnivorous pitcher plant) as
a model plant makes the following cross. She proceeds to take a wild type pure-breeding
female pitcher plant trisomic for chromosome 2 and crosses it to a normal diploid male pitcher
plant that is homozygous for a recessive mutation (v) that makes it hungry all the time (the
super hungry mutant). A trisomic F1 plant is then back-crossed to the super-hungry male
parent. From this cross:
A] What is the ratio of normal pitcher plants to those that are super hungry when you assume
that v is located on chromosome 2?
B] What is the ratio of normal pitcher plants to those that are super hungry when you assume
that v is not located on chromosome 2?

the observation that identical genotypes express similar phenotypes in different envirnoments ins an indication that
a. environment components have a large effect on the expression of the phenotype
b. this phenotype is not multifactorial
c. the genotype is for a single gene
d. the environment is equally important to the phenotype as the genotype
e. the phenotype is multifactorial but the genotype strongly influences the phenotype
select and support the most appropriate response and explain why each of the incorrect statements is eliminated

allele of a gene
a. are located in various locations of a chromosome
b. originate through mutation
c. always create a variant of the gene's protein detectable in the phenotype
d. differ in a person's gene pool
e. are different on sister chromatids in mitosis
select and support the most appropriate response, and explain why each of the incorrect statements is eliminated.