| I: | In ecology, the term “niche” describes the role an organism plays in a community. |
| II: | A species’ niche encompasses both the physical and environmental conditions it requires and the interactions it has with other species. |
| 1. | is the primary producer. |
| 2. | has no significant impact on the community. |
| 3. | plays a crucial role in maintaining community structure. |
| 4. | is a rare species that must be preserved immediately. |
| Assertion(A): | The logistic growth model is considered a more realistic one for a population growing under natural conditions. |
| Reason (R): | Resources for growth for most animal populations are finite and become limiting sooner or later. |
|
1. |
Both (A) and (R) are True and (R) correctly explains (A). |
|
2. |
Both (A) and (R) are True but (R) does not correctly explain (A). |
|
3. |
(A) is True; (R) is False |
|
4. |
Both (A) and (R) are False |
| 1. | the population grows in an exponential or geometric fashion |
| 2. | the population grows in an arithmetic fashion |
| 3. | the population stops growing in size |
| 4. | the population declines in size |
| 1. | an organism inflicts harm to another organism without any costs or benefits received by itself. |
| 2. | two species interact but do not affect each other. |
| 3. | one organism benefits and the other organism is neither benefited nor harmed. |
| 4. | species derive a mutual benefit. |
| I: | act as ‘conduits’ for energy transfer across trophic levels |
| II: | keep prey populations under control |
| III: | help in maintaining species diversity in a community |
Consider the given two statements:
|
Assertion (A): |
Predators in nature are ‘prudent’. |
|
Reason (R): |
Prey species have evolved various defenses to lessen the impact of predation |
|
1. |
Both (A) and (R) are True and (R) correctly explains (A). |
|
2. |
Both (A) and (R) are True but (R) does not correctly explain (A). |
|
3. |
(A) is True; (R) is False |
|
4. |
Both (A) and (R) are False |
| I: | For plants, herbivores are the predators. |
| II: | Nearly 75 percent of all insects are known to be phytophagous. |
| III: | Thorns in plants are the most common morphological means of defense against herbivory. |
| IV: | Cardiac glycosides produced by certain plants can be very detrimental to the health of herbivores. |