What proportion of the population is heterozygous (Bb) for this trait?

Once transcribed, eukaryotic mRNA typically undergoes substantial alteration that results primarily from

A large population of laboratory animals has been allowed to breed randomly for a number of generations. After several generations, 49 percent of the animals display a recessive trait (bb), the same percentage as at the beginning of the breeding program. The rest of the animals show the dominant phenotype, with heterozygotes indistinguishable from the homozygous dominants. What is the frequency of allele b in the gene pool?

Each set of lettered choices below refers to the numbered words or statements immediately following it. Select the one lettered choice that best fits each word or statement. A choice may be used once, more than once, or not at all in each set. Members of which species are herbivores?

This question refers to an experiment that is set up to determine the relative volume of O2 consumed by germinating and nongerminating (dry) pea seeds at two different temperatures. The change in volume is detected by using a respirometer over a given period of time. The data are given below.The rate of oxygen consumption in germinating pea seeds at 26°C is

According to fossil records and recent published observations, two species of leaf eating beetles (species A and B) have existed on an isolated island in the Pacific Ocean for over 100,000 years. In 1964 a third species of leaf-eating beetle (species C) was accidentally introduced on the island. The population size of each species has been regularly monitored as shown in the graph above. Propose an explanation for the pattern of population density observed in species C. Describe the effect that the introduction of beetle species C has had on the population density of species A and species B. Propose an explanation for the patterns of population density observed in species A and in species B. Predict the population density of species C in 2014. Provide a biological explanation for your prediction. Explain why invasive species are often successful in colonizing new habitats.

A major distinction between prokaryotes and eukaryotes is the presence of membrane-bound organelles in eukaryotes. Describe the structure and function of TWO eukaryotic membrane-bound organelles other than the nucleus. Prokaryotic and eukaryotic cells have some non-membrane-bound components in common. Describe the function of TWO of the following and discuss how each differs in prokaryotes and eukaryotes. DNA Cell wall Ribosomes Explain the endosymbiotic theory of the origin of eukaryotic cells and discuss an example of evidence supporting this theory.

Two fossil vertebrates, each representing a different class, are found in the undisturbed rock layers of a cliff. One fossil is a representative of the earliest amphibians. The other fossil, found in an older rock layer below the amphibian, is most likely to be

If a segment of DNA is 5′-TAC GAT TAG-3′, the RNA that results from the transcription of this segment will be

If a segment of DNA is 5′-TAC GAT TAG-3′, the RNA that results from the transcription of this segment will be