A population which exceeds its carrying capacity and then collapses is represented graphically as a?
- A. bell shaped curve
- B. skewed curve
- C. s-shape curve
- D. linear curve
The order of primary succession by plants in a very dry habitat is?
- A. xerophytes → mesophytes shrub
- B. mesophytes → xerophytes → shrub
- C. mesophytes → shrub -> xerophytes
- D. xerophytes → shrub → mesophytes
The effect of chlorofluorocarbon is
- A. reduction of oxygen concentration in the atmosphere
- B. depletion of the ozone layer
- C. screening of ultra violet rays
- D. increase in carbon dioxide concentration
The major pollutant around airport residential areas is
- A. oil spillage
- B. soot
- C. noise
- D. dust
Which of these values in kj/m2 likely represents the energy content of the producers in a habitat?
- A. 5033
- B. 100
- C. 12
- D. 10
The amount of energy passed from one trophic level to the next decreases because
- A. many organisms are present at the first trophic level
- B. many organisms occur at the higher trophic level
- C. more energy is conserved at lower trophic levels
- D. parts of the organisms remain unutilised at each trophic level
Wind speed is measured with
- A. a maximum-minimum thermometer
- B. a hygrometer
- C. a wet and dry bulb hygrometer
- D. an anemometer
Which of the following organisms are the producers in an aquatic habitat?
- A. Benthons
- B. Phytoplanktons
- C. Zooplanktons
- D. Nektons
The term community is defined as
- A. the different groups of plants and animals in the same area and interacting with each other
- B. the consumers and producers living in a habitat
- C. living organisms interacting with physical factors of an environment
- D. animals which mutually derive benefit from their association.
Which of the following features of the tadpole indicates that the animal is herbivorous? Possession of
- A. operculum
- B. muscular tail
- C. long coiled intestine
- D. internal gills
Which of the following protozoans feeds parasitically
- A. Paramecium
- B. Chlamydomonas
- C. Plasmodium
- D. Euglena
Which of the following enzymes does not belong to proteases?
- A. Sucrase
- B. Pepsin
- C. Trypsin
- D. Erepsin
Which of the following enzymes is not one of the main classes of enzymes?
- A. Sucrase
- B. Amylases
- C. Proteases
- D. Lipases
Use the following equations to answer the question below
I – Boiled saliva + starch → X
II – Fresh saliva + starch → Y
What substances do X and Y represent?
- A. X = Maltose and Y = Sugar
- B. X = Starch and Y = Maltose
- C. X = Sugar and Y = Starch
- D. X = Maltose and Y = Starch
Enzymes can be inactivated by certain chemical substances in the body called
- A. catalysts
- B. inhibitors
- C. substrates
- D. activators
‘The colour that is associated with a positive iodine test is
- A. brown
- B. red
- C. blue-black
- D. yellow
In a test for non-reducing sugars like sucrose, what is the significance of adding dilute hydrochloric acid to the original sugar solution? To
- A. hydrolyse the non-reducing sugar
- B. accelerate he rate of the reaction
- C. stabilize the medium
- D. sterilize the solution
Biuret’s test is carried out on a food substance to indicate the presence of
- A. vitamins B
- B. fats
- C. proteins
- D. starch
Micronutrients essential for the synthesis of chlorophyll include
- A. iron and potassium
- B. iron and magnesium
- C. magnesium and calcium
- D. magnesium and potassium
The mode of nutrition common to green plants is
- A. autotrophic
- B. heterotrophic
- C. holozoic
- D. saprophytic
In testing for starch in a leaf, the leaf is boiled in alcohol to
- A. kill the cells
- B. soften the leaf
- C. enable chemicals penetrate the leaf
- D. decolourise the leaf