In an ecosystem the organism which changes light energy into stored chemical energy is the

A. consumer

B. decomposer

C. producer

D. carnivore

Which of the following processes does not contribute to the maintenance of the nitrogen content of the soil?

A. Decomposition

B. Denitrification

C. Nitrification

D. Nitrogen fixation

Which of the following organisms is well adapted for fluid feeding?

A. Cockroach

B. Mosquito

C. Grasshopper

D. Ants

The density-dependent factors that operate to regulate a population size may include the following except

A. shortage of food supply

B. fire outbreak

C. spread of diseases

D. increased competition

Which of the following infections is unlikely to respond to antibiotic treatment?

A. Typhoid fever

B. Ring worm

C. Measles

D. Tetanus

Algal bloom depletes oxygen content of bodies of water polluted by

A. industrial effluents

B. thermal plant discharge

C. raw sewage disposal

D. crude oil spillage

Conservation of wild life is necessary mainly because

A. wild species cannot resist disease better than their domesticated species

B. many predator wild animals help in control of pests

C. many people derive pleasure from observing wild animals

D. it helps to prevent extinction of species

Which of the following is not a means of conservation?

A. Controlling excessive deforestation

B. Prevention of poaching

C. Replacing harvested mature trees with seedlings

D. Burning of vegetation before cropping

Which of the following statements about mutation is true?

A. The genotype is not affected

B. The genotype is affected

C. The phenotype is not affected

D. It cannot be induced by artificial means

Variation which exhibits a wide range from one extreme to the other with very little difference between the intermediates is described as

A. phenotypic

B. discontinuous

C. continuous

D. genotypic