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

The mineral that is most likely to be leached from the soil in case of rain would be:
1. ${\mathrm{Mg}}^{++}$
2. ${\mathrm{H}}^{+}$
3. ${\mathrm{Ca}}^{++}$
4. ${\mathrm{NO}}^{3-}$

Phytoremediation is:
1. concentrating minerals in rhizosphere.
2. minimizing soil erosion in arid lands.
3. nitrogen fixation by symbiotic bacteria in root nodules.
4. removal of heavy metals from polluted sites.

When nitrates are scarce in the soil where legumes are growing:
I. The plants secrete Nod factors that attract Rhizobia to their root hairs.
II. In turn the bacteria secrete flavonoids that stimulate the infection process in the plant.
1. Both I and II are correct
2. Only I is correct
3. Only II is correct
4. Both I and II are incorrect

The uptake of which of the following by a plant contributes maximum to its dry weight:
1. water and minerals through root hairs.
2. water and minerals through mycorrhizae.
3. carbon dioxide by leaves through stoma.
4. sugars in the root hairs.

What percentage of the dry weight of a plant is made up of organic molecules?
1. 10%
2. 23%
3. 72%
4. 96%

Protein malnutrition is a serious problem in developing countries. If the essential amino acids in crop plants for human consumption can be increased, it can help to overcome this problem. The best method to produce such crop plants is by:
1. breeding for higher yield of deficient amino acids.
2. increasing the amount of NPK fertilizer used on fields.
3. creating mutants that do not form symbiotic relationship with microbes.
4. transferring nitrogen fixing genes to plants through genetic engineering.

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

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.

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