(03.06 mc)

which of the following is true regarding the expression of a chromosomal genetic mutation that is expressed on a recessive allele? (1 point)

a. the mutation will be expressed only in individuals that are heterozygous for the gene.

b. the mutation will be expressed approximately 50 percent of the time.

c. the mutation will be expressed consistently when the mutation occurs on a recessive allele.

d. the mutation will be expressed only if the individual has two copies of the recessive allele.

Juan and carol were studying invertebrates in biology. they knew that segmented or earth worms preferred a dark, moist habitat. during this lab, they would be investigating the responses of organisms called planaria or dugesia tigrina. these were simple flatworms that still had a one-way digestive system and a very simple nervous system. juan and carol placed the planaria in a petri dish containing cool, distilled water that was partially covered with black paper. they shined a light on the dish. next, they removed the paper and placed a small amount of chicken liver at one end of the dish. they added a few large salt crystals to the water. finally, they added drops of hot water to the cool water in the petri dish. their results can be seen in the data table. according to their experiment, all but one conclusion is valid.