Which of the following helps differentiate essential thrombocythemia (ET) from primary myelofibrosis (PMF)?

60-year-old patient visited his general practitioner because of fatigue and unexplained bruising.  Physical examination revealed a frail, thin, pale man with widespread bruising.  A CBC was ordered and revealed abnormal granularity of platelets and leukocytes.  Red cells appeared dimorphic.  Bone marrow analysis showed 20% ringed sideroblasts with dysplastic changes in RBC and WBC precursors.  No cytogenetic abnormalities were detected.  Based on this information, what is a probable diagnosis?

Properly diagnosing a patient requires distinguishing the correct disorder from other disorders with a similar lab presentation. Which disorder below will present with leukocytosis?

A 60-year-old patient with headaches, pruritus after bathing, and blurred vision is suspected of having polycythemia vera. Which of the following supports this diagnosis?

What is the best interpretation of the flow cytometry data?

Which genetic mutation is most commonly associated with primary eosinophil disorders?

When only a very few individuals give rise to a new population in a new area of favorable habitat, the new population might possess different genotype frequencies for a certain trait than the larger population from which it separated. This is called the _________ effect.

Two bacteria (A and B) can both metabolize glucose, but bacterium A has developed an enzyme which can convert fructose into glucose whereas bacteria B does not. Why does bacterium A have a survival advantage over bacterium B?

The mode of natural selection in which one extreme phenotype is most fit and the environment selects against all other phenotypes is:

Within a population, the entire collection of genes and their alleles is the population’s: