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.

Secondary storage therefore needed because it is non-volatile, meaning it retains its contents without the need for a power supply. It also has the large storage capacity needed to store the operating system and all the programs and files needed by a modern computer system.

August 29, 1995 was for the first time declared National Sports Day, it being the 90th birthday of hockey wizard Dhyan Chand

Of the two international ship canals, the Suez is more important than the Panama. Constructed over a period of 10 years according to a plan of the French Engineer  Ferdinand de Lesseps, the Suez Canal was opened as early as 1869.

Nuclear Power Plant uses a Non Renewable Energy Source.

Non-renewable energy is that source of energy which can not be used again and again. This sort of energy is sustainable to exhaustion.

Non renewable energy is that form of energy which is subject to deletion. This type of energy is of many uses to us. It can be used to produce electricity, heating, cooking, transportation and manufacturing. 85% of the energy used in the industrial processes is form the non-renewable type of energy.