Assertion: Negatively charged ions in soils are more easily lost by leaching than positively charged ions.
Reason: Soil particles in most productive soils are positively charged.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

1. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
2. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
3. If the assertion is true but the reason is false
4. If both the assertion and reason are false

Assertion: High acidic soils can present problems for plant growth.
Reason: At low pH, aluminum ions toxicity becomes important.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: Young seedlings frequently show mineral deficiency symptoms.
Reason: Their requirement is much lower than the requirements of older plant parts.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: Legume roots not colonized by Rhizobium do not synthesise leghemoglobin.
Reason: Some leguminous plants do not need nitrogen as an essential macronutrient.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: Oxygenic photosynthetic bacteria (cyanobacteria) generate oxygen as a by-product of photosynthesis, yet some are able to fix nitrogen as well.
Reason: These are colonial bacteria that have specialized cells (heterocysts) that lack the oxygen generating steps of photosynthesis.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Assertion: Carnivory is an evolutionary last resort when nitrogen and phosphorus are limited in an ecosystem.
Reason: Large amount of energy and resources are allocated to carnivorous adaptations.

1. Both assertion and reason are true and the reason is the correct explanation of the assertion.
2. Both assertion and reason are true but the reason is not the correct explanation of the assertion.
3. Assertion is true but reason is false.
4. Both assertion and reason are false.

Plant growing in absence of light will show increased:
1. uptake of minerals
2. uptake of water
3. elongation of internodes
4. ascent of sap

Carnivorous plants are almost entirely restricted to habitats like bogs where:

1. soil nutrients are extremely limiting, but where sunlight and water are readily available.

2. soil has very low nitrogen but other minerals are adequate and there is shortage of sunlight.

3. soil nutrients, sunlight and water are all in very limited supply.

4. soil nutrients are readily available, but where sunlight and water are extremely limiting.

Consider the following two facts regarding mycorrhizae:
A. The percent of plant species that form ectomycorrhizae
B. The percent of plant species that form arbuscular mycorrhizae

1.(A) is greater than (B)
2. Item (A) is less than item (B)
3.(A) and (B) are approximately equal
4. A & B have no relationship

The property of soil that is least conducive to plant growth would be:
1. a large percent of humus content
2. a large number of soil organisms
3. a compacted soil
4. a soil with high porosity