Cochineal insects have proved very useful for
rodents control
Parthenium control
cactus prevention
Eicchornia prevention
C.
cactus prevention
In India and Australia, the overgrowth of cacti was checked by the introduction of cochineal insect (Cactoblastis cactorum).
Select the option that correctly matches characteristic features with the group of three animals.
Skeleton ofspicules - Sycon, Adamsia, Spongilla
Excretion by flame cells - Taenia, Fasciola, Ancylostoma
Mouth contains radula - Dentalium, Octopus, Ophiura
Jointed appendages - Limulus, Apis, Laccifer
Some salient features and phyla of organisms are given below. Select the option which shows correct combination of organism, its phylum and salient features.
Benthoic animals are those, which
are deep dweller in sea
are floating (free) organisms
are submerged in sea
float on the sea surface
Which of the following waste products in grasshopper is not excreted and is used in other metabolic activities
Carbon dioxide
Water
Uric acid
Faeces
The formation of canal system in sponges is due to
reproduction
porous walls
folding of inner walls
gastro- vascular system
Assertion: Cephalisation is advantageous to an animal.
Reason: Cephalisation improves the appearance of an animal.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
Assertion: The nymph of a cockroach undergoes moulting several times.
Reason: There is gradual metamorphosis in cockroach.
If both assertion and reason are true and reason is the correct explanation of assertion.
If both assertion and reason are true but reason is not the correct explanation of assertion.
If assertion is true but reason is false.
If both assertion and reason are false.
