52) Mendel’s contribution to genetics was the discovery of DNA.

53) Mendel’s crosses with pea plants disproved the notion that, when individuals with two different traits are mated, the genetic information blends in the offspring and is not retained as separate elements.

54) If a person has a recessive trait, the genotype must be homozygous recessive for the trait.

55) When two individuals with different traits are crossed, either the dominant or the recessive trait, and not an intermediate trait, is always seen, no matter what the organism or phenotype.

Match the following.

A) Alleles come in dominant and recessive forms.

B) There is no “blending” in inheritance.

C) Neither allele is completely dominant over the other.

D) Genes assort independently in gamete formation.

56) When true-breeding P plants of different types are crossed, the offspring do not have a phenotype intermediate between the two parents.

57) When true-breeding P plants are crossed, all offspring have the trait of one of the parents.

58) When two traits are followed in a dihybrid cross, heterozygotes in the F1 generation produce offspring with all combinations of phenotypes, in a 9:3:3:1 ratio.

59) The crossing of two true-breeding parents seems to produce a blending in the F1 generation, but the dominant and recessive traits are expressed again in the F2 generation.

60) The physical characteristics of an organism, or its ________, are determined by its genetic makeup, referred to as its ________.

61) A particular quality of an organism is referred to as a ________, each variation of which is a particular ________.

62) In the Law of ________, Mendel stated that two genetic elements are separated in gamete formation.

63) If a plant heterozygous for the genes for both seed color and shape is self-fertilized, the ratio of offspring with smooth, green seeds is ________/16. (Yellow and smooth are the dominant phenotypes.)

64) A true-breeding strain of red tulips is crossed to a true-breeding strain of white tulips. All the offspring have pink flowers. When a pink-flowered plant is self-fertilized, the offspring have red, pink, and white flowers, in the ratio 1:2:1. This type of inheritance is an example of ________.