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149)

List two diseases that are caused by a recessive allele? Answer:

150)

Sickle-cell anemia, cystic fibrosis, Tay-Sachs Phenylketonuria, Thalassemia.

In corn liguleless, (l) is recessive to ligules (L) and a green leaf (G) is dominant to the normal non-green (g). If a plant homozygous for liguleless and green leaves is crossed to one homozygous for non-green with ligules, predict the phenotypes and genotypes of the F 2. Answer:

# Genotype 1 LLGG 2 LLGg 2 LlGG 4 LlGg 1 LLgg 2 Llgg 1 llGG 2 llGg 1 llgg 151)

Phenotype Ligules/Green Ligules/Green Ligules/Green Ligules/Green Ligules/Non-green Ligules/Non-green Liguleless/Green Liguleless/Green Liguleless/Non-green

Stem colour of tomato plants is known to be under the genetic control of at least one pair of alleles such that A_ results in the production of anthocyanin pigment (purple stem). The recessive genotype aa lacks this pigment and hence is green. The production of two locules (seed chambers) in the tomato fruit is controlled by the dominant allele M, and multiple locules is determined by mm. Determine the genotypic and phenotypic ratios of the F2 offspring beginning with a parental cross between an inbred tomato plant that has a purple stem and fruit with two locules, and a tomato plant that has a green stem and fruit with multiple locules. Assume independent assortment. Answer:

# 1 2 2 4 1 2 1 2 1

Genotype AAMM AaMM AAMm AaMm aaMM aaMm AAmm AAMm aamm

Phenotype Purple, 2 locules Purple, 2 locules Purple, 2 locules Purple, 2 locules Green, 2 locules Green, 2 locules Purple, Multi locules Purple, Multi locules Green, Multi locules

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Test Bank for Genetics 2nd Hartwell  

Test Bank Genetics 2nd Edition Hartwell 2017 (Test Bank Download) (9781259370885) (1259370887). Instant access. All chapter are included. Al...

Test Bank for Genetics 2nd Hartwell  

Test Bank Genetics 2nd Edition Hartwell 2017 (Test Bank Download) (9781259370885) (1259370887). Instant access. All chapter are included. Al...