In a certain plant, when individuals with blue flowers are crossed with individuals with blue flowers, only blue flowers are produced. Plants with red flowers crossed with plants with red flowers sometimes produce only red flowers, although other times they produce either red or blue flowers. When plants with red flowers are crossed with plants with blue flowers, sometimes only red flowers are produced; other times either red or blue flowers are produced. Which of the following is true?

In horses, black coat color is influenced by the dominant allele (B), and chestnut coat color by the recessive allele (b). Trotting gait is due to a dominant gene (T), pacing gait to the recessive allele (t). Give the phenotype and genotype of the horse you would use in a testcross to determine the genotype of a black trotter.

Spindles are ___.

Which phase(s) of meiosis occur in a similar manner to mitosis?

Pairs of maternal and paternal chromosomes line up between the two spindle poles during _______________.

In radishes, long or round are homozygous forms of an incompletely dominant gene, and oval is the phenotype of the heterozygote. If a long radish is crossed with a round radish, which of the following phenotypic ratios of the F2 generation is correct?

Protein products of which genes “put the brakes” on the cell cycle when DNA is damaged or incompletely copied?

In tomatoes, red (R) is dominant to yellow (r), tall (D) is dominant to dwarf (d), and smooth (H) is dominant to hairy (h). How many possible different phenotypes are there in relationship to these three characteristics?

Stress-induced depression has been found to be a result of which of the following?

In humans, environmental factors causing stress can impact