2007 - WAEC Biology Past Questions and Answers - page 4
31
Enzymes can be inactivated by certain chemical substances in the body called
A
catalysts
B
inhibitors
C
substrates
D
activators
correct option: b
Enzyme inhibitors are substances which alter the catalytic action of the enzyme and consequently slow down, or in some cases, stop catalysis.
32
Use the following equations to answer the question below
I - Boiled saliva + starch → X
II - Fresh saliva + starch → Y
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
correct option: b
Users' Answers & Comments33
Which of the following enzymes is not one of the main classes of enzymes?
A
Sucrase
B
Amylases
C
Proteases
D
Lipases
correct option: a
Users' Answers & Comments34
Which of the following enzymes does not belong to proteases?
A
Sucrase
B
Pepsin
C
Trypsin
D
Erepsin
correct option: a
Users' Answers & Comments35
Which of the following protozoans feeds parasitically
A
Paramecium
B
Chlamydomonas
C
Plasmodium
D
Euglena
correct option: c
Users' Answers & Comments36
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
correct option: c
Users' Answers & Comments37
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.
correct option: a
Users' Answers & Comments38
Which of the following organisms are the producers in an aquatic habitat?
A
Benthons
B
Phytoplanktons
C
Zooplanktons
D
Nektons
correct option: b
Users' Answers & Comments39
Wind speed is measured with
A
a maximum-minimum thermometer
B
a hygrometer
C
a wet and dry bulb hygrometer
D
an anemometer
correct option: d
Users' Answers & Comments40
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
correct option: d
Users' Answers & Comments