Questions

Metamorphism is the method of changing the structure of a rock by using heat and temperature.

Hence, for this to happen the parent rock must be in solid form only. Therefore, option C) is true.

Geography is a field of science related to the study of the lands, places, relation between people & their environments. Geography can be understood in terms of five different themes. They are :

• Location
• Place
• Human-Environment Interaction (HEI)
• Movement
• Region.

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.

The calm centre of the anticyclonic gyre in the North Atlantic, comprising a large eddy of surface water, the boundaries of which are demarcated by major current systems such as the Gulf Stream, Canaries Current, and North Atlantic Drift. The Sargasso Sea is a large, warm (18°C), saline, which is characterized by an abundance of floating brown seaweed (Sargassum).

The world's most valuable company is Apple followed by Amazon and Microsoft.