Free Forest Ecology MCQs with Answers

• A. Plentiful xylem and sclerenchyma
• B. Abundant air spaces and air chambers
• C. Leaves having stomata only on the upper side or none
• D. Poor development of roots

Explanation: Hydrophytes typically have extensive air spaces, reduced roots, and reduced supporting tissues because water provides support.

• A. Hydrophytes
• B. Mangroves
• C. Mesophytes
• D. Xerophytes

Explanation: Mangroves are salt-tolerant woody plants forming tidal forests in marshy coastal saline habitats.

• A. In sandy soil
• B. On gravels
• C. In clay soil
• D. In loamy soil

Explanation: Clay soils have very small pores and poor drainage, so water accumulates when drainage is inadequate, producing waterlogging.

• A. Nowhere on the plant
• B. Lower surface of the leaf
• C. Both the surfaces of the leaf
• D. On upper surface of the leaf

Explanation: Submerged leaves generally lack functional stomata because gases can diffuse directly across their thin surfaces from the surrounding…

• A. Harmful to the plants growing in the soil
• B. Both harmful as well as useful to plants growing on the soil
• C. Neither harmful nor useful to plants growing in the soil
• D. Useful to plants growing in the soil

Explanation: Soil organisms include beneficial decomposers and nitrogen-fixing microbes, but also harmful pathogens and pests.

• A. Physically dry soils
• B. Physiologically dry soils
• C. Alkaline soils
• D. Acidic soils

Explanation: Waterlogged soil contains abundant water, but oxygen deficiency prevents roots from absorbing and using it normally, producing a…

• A. Free floating hydrophyte
• B. Suspended hydrophyte
• C. Submerged hydrophyte
• D. Floating and anchored hydrophyte

Explanation: Hydrilla remains completely below the water surface and is rooted in the bottom mud, making it a submerged hydrophyte.

• A. Hygroscopic water
• B. Run away water
• C. Capillary water
• D. Gravitational water

Explanation: Hygroscopic water forms an extremely thin film around soil particles and is held so tightly that plant roots generally cannot absorb it.

• A. Wet habitats
• B. Dry habitats
• C. Warm habitats
• D. Cool habitats

Explanation: A thick cuticle reduces evaporation from the leaf, so it is a typical xerophytic adaptation to dry habitats.

• A. Oxylophytes
• B. Halophytes
• C. Psychrophytes
• D. Psammophytes

Explanation: Psychrophytes are plants adapted to very low temperatures and cold soils.

• A. Thick cuticle
• B. Well developed conducting tissue
• C. Well developed mechanical tissue
• D. Spongy paraenchyma

Explanation: Xerophytes commonly develop thick cuticles and strong conducting and mechanical tissues to conserve water and withstand drought.

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

Explanation: Euphorbia, Acacia and Aloe are dicotyledonous plants, whereas Vallisneria is a monocotyledonous aquatic plant.

• A. Well developed sclerenchyma
• B. Cuticle
• C. Air spaces
• D. Well developed vascular tissues

Explanation: Submerged hydrophytes develop large air spaces, or aerenchyma, which help internal aeration and buoyancy in water.

• A. Field capacity
• B. Field capacity less capillary water
• C. Field capacity plus gravitational water
• D. Field capacity less hygroscopic water

Explanation: The soil-water storage available to plants is estimated as field capacity minus hygroscopic water.

• A. Spines
• B. Stolons
• C. Scales
• D. Phylloclades

Explanation: In Opuntia, leaves are reduced to spines to limit water loss and protect the plant.

• A. Otherwise the weight of these tissues would drown the plant
• B. Water provides the support and there is no problem for the absorption and conduction of water
• C. Of the anaerobic conditions created by submergence
• D. Otherwise translocation of food would have been interrupted

Explanation: Hydrilla is surrounded by water, which provides external support, and water is readily available for absorption and conduction.

• A. Tropical rain forests
• B. Deciduous forests
• C. Deserts
• D. Tundras

Explanation: Succulents store water in thick, fleshy leaves or stems, an adaptation especially useful in deserts.

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

Explanation: Rhizophora and Avicennia are characteristic mangrove plants adapted to saline, waterlogged coastal habitats.

• A. Capillary water plus hygroscopic water
• B. Capillary water
• C. Hygroscopic water
• D. Gravitational water

Explanation: Field capacity is the soil moisture remaining after excess gravitational water has drained away, consisting chiefly of capillary water…

• A. Well developed stomata
• B. Well developed root system
• C. Well developed aerenchyma
• D. Well developed vascular system

Explanation: Hydrophytes commonly possess a well-developed aerenchyma system, whose air spaces facilitate gas exchange in waterlogged tissues.