What is the best pH of soil for cultivation?

A. 3.8-5.4
B. 6.5-7.5
C. 4.5-8.5`
D. 5.5-6.5

The percentage of argon in the atmosphere is:

A. About 1%
B. 0.35%
C. 0.90%
D. 3%

Which of the following are plants of one group?

A. Mangifera and Rhizophora
B. Rhizophora and Avicennia
C. Rhizophora and Balanophora
D. Avicennia and Balanophora

Mycorrhiza is the:

A. Saprophytic association between fungus and the roots of seed plants
B. Parasitic association between fungus and the roots of seed plant
C. Symbiotic association between fungus and the roots of seed plants
D. All of the above

The first plants to reappear in a badly burnt forest area will most probably be:

A. Mosses
B. Liverworts
C. Ferns
D. Grasses

Mycorrhiza is an example of:

A. Decomposers
B. Endoparasitism
C. Ectoparasitism
D. Symbiotic relationship

Among the plants listed, point out one that does not fit into biological group represented by other plants

A. Euphorbia
B. Acacia
C. Vallisneria
D. Aloe

Useful adaptation of hydrophytes is:

A. Large leaves
B. Decrease in mechanical tissue
C. Large mechanical tissue
D. Increase in aerenchyma

The transition zone between two different types of communities is called:

A. Biome
B. Ecotone
C. Biological spectrum
D. Biological clock

The heliophytes are characterised by:

A. High OP, high K+ conc
B. High OP, low K+ conc
C. Low OP, low K+ conc
D. Low OP, high K+ conc