Which of the following is not a means of conserving natural resources?
Establishment of national parks
Selective logging
Building of dams
Bush burning
Correct answer is D
No explanation has been provided for this answer.
Viruses are economically important because they?
do not have cell structures
can only reproduce inside living cells
cause diseases in plants and animals
exist as crystals outside living cells
Correct answer is C
Plant viruses are of considerable economic importance because many of them infect crop and ornamental plants.
Numerous plant viruses are rodlike and can be extracted readily from plant tissue and crystallized.
Animal viruses of economic importance: Genetic variation, persistence, and prospects for their control.
The major reason why foods should be properly covered is that
micro-organisms in air would contaminate the food
hot foods cool off easily when properly covered
the taste of the food is maintained when covered
all water easily evaporates from uncovered food
Correct answer is A
No explanation has been provided for this answer.
kingdom
class
family
species
Correct answer is B
No explanation has been provided for this answer.
Trypanosomiasis is associated with
cockcroach
mosquito
housefly
tsetse fly
Correct answer is D
No explanation has been provided for this answer.