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
Which of the following infections is unlikely to respond to antibiotic treatment?
- A. Typhoid fever
- B. Ring worm
- C. Measles
- D. Tetanus
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 organisms is well adapted for fluid feeding?
- A. Cockroach
- B. Mosquito
- C. Grasshopper
- D. Ants
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
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 instruments is used to measure the speed of a stream?
- A. Simple float
- B. Secchi disc
- C. Quadrat frame
- D. Rain gauge
Which of the following factors is not associated with aquatic habitats?
- A. Salinity
- B. Turbidity
- C. Temperature
- D. Edaphic
A stable self-sustaining environment produced by an interaction between the biotic and abiotic components is best described as
- A. a niche
- B. a community
- C. an ecosystem
- D. a habitat
Possession of strong adhesives is a feature of animals living in/on
- A. sandy beaches
- B. rocky shores
- C. benthic zones
- D. deserts
A population is best described as
- A. a group of the same species of organisms living together
- B. a group of animals and plants living together
- C. a group of insects and grasses
- D. different species of wild animals
In the marine food web, the source of energy to the producer comes from
- A. sea waves
- B. sea water
- C. sun
- D. air
Trees in savannah habitats usually have heavy thick bark which mainly
- A. reduces the rate of transpiration
- B. protect them from the scorching sun
- C. protect them from heavy winds
- D. resist bush tires
Which of the following juices contains the enzyme ptyalin?
- A. Gastric juice
- B. Pancreatic juice
- C. Succus
- D. Saliva
Which of the following elements is required in large amounts by plants
- A. Molybdenum
- B. Boron
- C. Copper
- D. Phosphorus
Which of the following substances has the highest amount of energy in joules per unit weight?
- A. Carbohydrates
- B. Proteins
- C. Fats
- D. Vitamins
Which of the following elements is required in large amounts by plants
- A. Molybdenum
- B. Boron
- C. Copper
- D. Phosphorus
Which of the following statements is not true of the light stage of photosynthesis?
- A. Chlorophyll is energized by sunlight
- B. Water molecules split into hydrogen and hydroxyl ions
- C. Carbon (IV) oxide is reduced by hydrogen atoms in NADPH2
- D. Water is formed
When both ovaries of the human female ovulate simultaneously and both ova are fertilized, then
- A. identical twins are produced
- B. fraternal twins are produced
- C. Siamese twins are produced
- D. the children produced are genetically identical
Which of the following describes an example of fertilization in higher organisms?
- A. Fusion of sperm and egg nuclei
- B. Ejaculating of sperm into a female body
- C. Male gametes germinating in the pollen tube
- D. A pollen grain landing on a sticky stigma
Reading the verdict of a case by a judge or magistrate is an example of
- A. a reflex action
- B. an instinct
- C. a conditioned reflex
- D. a voluntary action