Questions

Parvovirus B19 causes severe anemia because it preferentially infects erythrocyte precursors.

a. Parvovirus B19 binds preferentially to the erythrocyte blood group P antigen on erythroid precursor cells.

Answers B, C, D are incorrect:

b. after entry the single-stranded viral DNA genome is transported to the cell nucleus where the host DNA polymerase synthesizes the complimentary DNA strand.

c. Parvovirus B19 infection can be diagnosed by direct detection of viral DNA not RNA.

d. the fetus of a seropositive mother is protected from infection by maternal circulating antibodies.

At the synapse between two neurons, electrical signals are converted into chemical signals. A synapse is the gap between the two neurons.

Study of Life in outer space or search of life external to Earth is known as Exobiology.

Executive Branch of government is responsible for enforcing laws.

The 4 components all computers have in common are Input, Output, Storage and Processing. 

A devastating  series of earthquakes in 1906 ruined the city completely and its presence is a constant remainder of the past and a threat of repetition in future.

Abraham Lincolon was an American statesman and lawyer who served as the 16th President of the United States from March 1861 until his assassination in April 1865.

Lincoln led the United States through the American Civil War—its bloodiest war and perhaps its greatest moral, constitutional, and political crisis.