In mice, black color (b) is dominant to white (b). at a different locus, a dominant allele (a) produces a band of yellow just below the tip of each hair in mice with black fur. this gives a frosted appearance known as agouti. expression of the recessive allele (a) results in a solid coat color. if mice that are heterozygous at both loci are crossed, what is the expected phenotypic ratio of their offspring? a. huntington's diseaseb. tay-sachs diseasec. phenylketonuriad. cystic fibrosise. sickle-cell disease

After reading the paragraph below, answer the questions that follow. researchers have created a robot that has a very thin leg that is moved by cardiac (heart) cells contracting in unison. the robot, made of a polymer similar to that used in making contact lenses, is bathed in heart cells with supporting cells, which then attach to the robot and provide movement as they contract. all of the cardiac cells working together can cause the robot leg to move in a way that individual cells could not. this is an example of a. emergent properties of cells. b. energy flow through an ecosystem. c. adaptation. d. internal environment regulation.

According to the cladogram, which organisms have roundworms as a common ancestor?

Which of the following observation darwin shape his concept of descent with modification? a) species diversity declines farther from the equator. b) fewer species live on islands than on the nearest continents. c) birds live on islands located farther from the mainland than the bird's maximum nonstop flight distance. d) south american temperate plants are more similar to the tropical plants of south america than to the temperate plants of europe. e) earthquakes reshape life by causing mass extinctions.