Assertion (A): | If introduced species evolved under great competition or predation in their native habitat, they are more likely to become invasive in the introduced habitat. |
Reason (R): | Then the new environment may host fewer able competitors, allowing the invader to proliferate quickly. |
In the light of the above statements, choose the most appropriate answer from the options given below :
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and reason are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
The most serious negative impact of loss of biodiversity on humans would be due to:
1. global warming and ozone depletion.
2. loss of ecosystem services.
3. loss of source of genetic diversity to preserve endangered species.
4. loss of species for ʺbioprospecting.ʺ
Assertion (A): | Certain exotic species, introduced into a geographical area, become invasive. |
Reason (R): | The exotic species that become invasive can only be plants that can reproduce asexually very rapidly. |
In the light of the above statements, choose the most appropriate answer from the options given below :
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | (A) is false but (R) is true. |
Assertion (A): | Island ecosystems are generally more prone to invasion by the introduced species. |
Reason (R): | Invasion is more likely in ecosystems that was similar to the one in which the potential invader evolved. |
1. | Both (A) and (R) are true and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are true but (R) is not the correct explanation of (A). |
3. | (A) is true but (R) is false. |
4. | Both (A) and (R) are false. |
.
Match each item in Column I with one in column II and select the correct answer from the codes given:
|
COLUMN I |
|
COLUMN II |
A |
Dodo |
P |
Bird |
B |
Thylacine |
Q |
Zebra |
C |
Quagga |
R |
Marsupial |
D |
Steller’s sea cow |
S |
Aquatic mammal |
Codes:
A |
B |
C |
D |
|
1. |
P |
Q |
R |
S |
2. |
P |
Q |
S |
R |
3. |
P |
R |
Q |
S |
4. |
S |
R |
Q |
P |
Which one of the following is an endangered plant species in India?
1. | Rauwolfia serpentine | 2. | Santalum album (Sandalwood) |
3. | Cycasbeddonel | 4. | All of these |
The most effective means of conservation is to:
1. remove predators
2. preserve habitats
3. vaccinate against diseases
4. census the species during the breeding season
Exotic alien introduced species can become invasive in the introduced ecosystem due to:
I. preying on native species.
II. out-competing native species for food, light, and breeding habitat.
III. lack of natural predators.
1. | Only I and II | 2. | Only I and III |
3. | Only II and III | 4. | I, II and III |
Which of the following is not a cause for the loss of biodiversity?
1. Destruction of habitat
2. Invasion by alien species
3. Keeping animals in zoological parks
4. Over-exploitation of natural resources
The peregrine falcon in the United States got extinct due to:
1. | loss of habitat | 2. | pesticides |
3. | loss of food supply | 4. | predation |