Nicotine, caffeine, quinine and opium produced by plants are actually:
1. | Primary metabolites needed in reproduction |
2. | Secondary metabolites needed for growth |
3. | Alkaloids that are present in seeds |
4. | Defenses against grazers and browsers |
Consider the given statements regarding competition amongst organisms:
I: | Only related species can compete for the same resource |
II: | Competition occurs only when the resources are limiting |
The correct statement/s is/are:
1. | I alone | 2. | II alone |
3. | Both I and II | 4. | Neither I nor II |
A process in which the fitness of one species is significantly lower in the presence of another species, is termed as :
1. | Predation | 2. | Parasitism |
3. | Competition | 4. | Amensalism |
Abingdon tortoise in Galapagos islands became extinct within a decade after goats were introduced on the island due to:
1. Habitat fragmentation
2. Better browsing efficiency of goats
3. Predator of goat attacking tortoise
4. Virus of goats parasitizing tortoise
“Competitive Exclusion Principle” may be true if:
1. | The competing species are equally capable |
2. | Resource partitioning occurs |
3. | There is only intraspecific competition |
4. | Resources are limiting |
One mechanism that promotes co-existence rather than exclusion amongst competing species is:
1. | Periodic migration | 2. | Hibernation and aestivation |
3. | Resource partitioning | 4. | Reproductive isolation |
Cuckoos laying their eggs in the nests of crow is an example of:
1. | Ectoparasitism | 2. | Endopararsitism |
3. | Hyperparasitism | 4. | Brood parasitism |
An orchid growing as an epiphyte on a mango branch is an example of:
1. | Ectoparasitism | 2. | Endopararsitism |
3. | Commensalism | 4. | Mutualism |
All the following relations are examples of commensalism except:
1. | Sea anemone and clown fish |
2. | Cattle egret and grazing cattle |
3. | Barnacles growing on the back of whale |
4. | Cuscuta growing on hedge plants |
In mycorrhiza, the fungi help the plant in:
1. Synthesis of high energy carbohydrates
2. Absorption of essential nutrients from the soil
3. Nitrogen fixation
4. Biocontrol of pathogens