An endangered species as compared to a threatened species:
1. is nearer to extinction
2. threatens the survival of other species
3. is one about which the known data is deficient
4. has more diversity
Apex predators also commonly act as:
1. | Keystone species | 2. | Tertiary consumers |
3. | Endemic species | 4. | Ecospecies |
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 |
Habitat loss and fragmentation lead to loss of biodiversity primarily because:
1. | less plants in fragmented habitats leads to less photosynthesis. |
2. | more soil erosion takes place in fragmented habitats. |
3. | smaller populations in fragmented habitats are more prone to extinction. |
4. | animals migrate out of smaller habitat fragments. |
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 |
Overexploitation is one of the “evil quartet” that increases the risk of extinction mainly for the:
1. animals that feed on a lower trophic level
2. large animals with low intrinsic reproductive rates
3. aquatic animals
4. terrestrial organisms
The biggest factor for the ‘biodiversity crisis' that we face today is:
1. Global warming
2. Environmental pollution
3. Habitat loss and fragmentation
4. A large and increasing human population
Consider three sample areas with the following composition:
Sample area I: | has three species of birds, two are represented by one individual each and the third by four individuals |
Sample area II: | has three species of birds, each represented by two individuals |
Sample area III: | has a species of insects, a species of mammals and a species of birds, each with two individuals |
Which area will be considered as the most diverse?
1. Sample area I
2. Sample area II
3. Sample area III
4. Sample area II and Sample area III are equally diverse
Regarding the gradients of biodiversity:
I: | As we move from poles to the equator, broadly speaking, biodiversity decreases. |
II: | There is an increase in species diversity from lower to higher altitudes. |
1. Only I is correct
2. Only II is correct
3. Both I and II are correct
4. Both I and II are incorrect
Plants are an important source of medicines for human use. Identify the incorrectly matched pair:
|
PLANT |
MEDICINE |
1. |
Taxusbrevifolia |
Anticancer drug |
2. |
Cinchona officinalis |
Anti-malarial |
3. |
Rauwolfiaserpentina |
Anti-hypertensive |
4. |
Catharanthusroseus |
Anti-helminthic |