Exam 19: Introduction to Genetics

If short hair (L) is dominant to long hair (l) , animals LL and Ll have the same

The appearance of the chins at #3 is called the

Congenital deafness in humans is due to the homozygous condition of either or both of the recessive genes d or e . Both dominant D and E are necessary for normal hearing. Gene D/d affects the middle ear, while gene E/e affects the inner ear. It does not matter how good the normal inner ear (as indicated by E _) is; if there is something wrong in the middle ear, the individual is unable to hear. The same applies for the other gene. Give the phenotypic results of the following crosses: (a) Dd EE x Dd EE (b) Dd Ee x Dd Ee (c) dd EE x DD ee (d) Dd EE x Dd ee (e) Dd EE x DD Ee

Each version of a gene is called a(n)

Tall ( D ) is dominant to dwarf ( d ). Give the F ₂ genotypic and phenotypic ratios of a cross between a pure-breeding, tall plant and a pure-breeding, dwarf plant.

In horses, there are four alleles at the A locus. Arranged in dominance sequence, they are: A (wild) a ^b (bay) a ^c (brown) a ^d (black) If you bred several bay mares whose sires were brown to a brown stallion whose sire was black, what type of offspring would be produced and in what proportion?

The wide-ranging effect of a single gene is called

A locus is

If a child has blood type AB, he or she could NOT have been produced by which set of parents?

The allele for albinism ( c ) is recessive to the allele for normal pigmentation ( C ). A normally pigmented woman whose father is an albino marries an albino man whose parents are normal. They have three children of which two are normal and one is albino. Give the genotypes for each person listed.

The probability that an individual who inherits an allele will have the phenotype associated with it is

If all the offspring of a testcross are alike and resemble the organism being tested, then that parent is

In cocker spaniels, black coat color (B) is dominant over red (b) , and solid color (S) is dominant over spotted (s) . If two black, solid dogs were crossed several times and the total offspring were eighteen black, solid and five black, spotted puppies, the genotypes of the parents would most likely be

In sweet peas, genes C and P are necessary for colored flowers. In the absence of either (__ pp or cc __), or both ( cc pp ), the flowers are white. What will be the color of the offspring of the crosses in what proportions for the following? (a) Cc Pp x cc pp (b) Cc Pp x Cc Pp (c) Cc PP x Cc pp (d) Cc pp x cc Pp

Independent assortment occurs during

In radishes, two incompletely dominant genes control color and shape. Red and white radishes are homozygous, while the hybrid is purple. Long and round are homozygous and, if crossed, will produce an oval hybrid. Give the F ₂ genotypic and phenotypic ratio produced by crossing pure-breed red and long radishes with white and round varieties.

In cocker spaniels, black coat color (B) is dominant over red (b) , and solid color (S) is dominant over spotted (s) . A cross of Bb Ss with bb ss would produce the phenotypic ratio

In cocker spaniels, black coat color (B) is dominant over red (b) , and solid color (S) is dominant over spotted (s) . If two dihybrids (Bb Ss) were crossed, what fraction of the black, solid offspring would be homozygous?

In cocker spaniels, black coat color (B) is dominant over red (b) , and solid color (S) is dominant over spotted (s) . If two dihybrids (Bb Ss) were crossed, which would be produced?

In sweet peas, genes C and P are necessary for colored flowers. In the absence of either (__  pp or cc  __), or both ( cc pp ), the flowers are white. Give the probable genotype of a plant with colored flowers and a plant with white flowers that produced 38 plants with colored flowers and 42 plants with white flowers.