Questions

Smooth Endoplasmic Reticulumdoes not contain ribosomes on its surface for which it is regarded as smooth. So, proteins cannotbe synthesised by SER provided protein synthesis is the primary task of ribosomes.

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.

Executive Branch of government is responsible for enforcing laws.

TRUTH TABLE FOR HALF ADDER

A    B  SUM  CARRY

0    0    0         0

0    1    1         0

1    0    1         0

1    1    0         1

INPLEMENTATION:

For SUM, The two inputs A and B are given to XOR gate.

For Carry, The two inputs A and B are given to AND gate.