Lecture 8

Question 1

Temperature-sensitive Allele

Answer 1

An allele whose product is functional only above or below a threshold temperature; Siamese cats have dark colored fur on their extremities because allele that controls pigment at the lower temperature of those extremities

Question 2

Discontinuous Characteristics

Answer 2

Relatively few phenotypes

Question 3

Continuous Characteristics

Answer 3

Continuous distribution of phenotypes; occurs when genes at many loci interact

Question 4

Polygenic Characteristics

Answer 4

Characteristics encoded by genes at many loci

Question 5

Heterosis (Hybrid Vigor)

Answer 5

The improved or increased function of any biological quality in a hybrid offspring of pure bred strains; the increase of heterozygosity improves such characteristics as size, growth rate, fertility, or yield of a hybrid organism over either of its parents