2011 - WAEC Biology Past Questions and Answers - page 5
41
The falling off of leaves of deciduous trees is helpful to the plant because it
A
reduces the rate of transpiration
B
enables the plant to conveniently eliminate its excretory products
C
enables the plant to bear more fruits
D
ensures that the limited mineral salts get to only growing regions
correct option: a
Users' Answers & Comments42
A sample of wet garden soil of known weigh was heated to constant weight. The loss of weight is due to loss of
A
water
B
organic matter
C
water and organic matter
D
water and inorganic matter
correct option: c
Users' Answers & Comments43
Assuming that a period of stable population size is followed by a period when natality increases by ten (1O) per cent and immigration increases by twenty (20) percent of population size. The population size will
A
be at equilibrium
B
increase by forty (40) per cent
C
begin to increase
D
begin to decrease
correct option: c
Users' Answers & Comments44
Which of the following methods does not make water fit for drinking?
A
Addition of chlorine
B
Boiling
C
Distillation
D
Addition of alum
correct option: c
Chlorine is one of the most commonly used disinfectants for water disinfection. Addition of Chlorine helps to kill certain bacteria and other microbes in tap water
Users' Answers & Comments45
Vaccination results in
A
aiding red blood cells to carry more oxygen
B
production of antibodies which destroy toxins of germs
C
arresting excessive bleeding
D
production of white blood cells which engulf and digest bacteria.
correct option: b
Users' Answers & Comments46
Leguminous crops are incorporated into crop rotation in order to
A
improve aeration of the soil.
B
promote nitrogen fixation
C
increase the rate of soil formation
D
improve upon the water holding capacity of the soil
correct option: b
Users' Answers & Comments47
Which of the following practices improves crop yield in a clayey soil? Addition of
A
more water and humus
B
lime and humus
C
fertilizers
D
weedicides and fertilizers
correct option: b
Users' Answers & Comments48
Which of the following activities promotes forest conservation?
A
Lumbering
B
Use of firewood for cooking
C
Afforestation
D
Production of paper
correct option: c
Users' Answers & Comments49
Which of the following statements is not true about continuous variation? It
A
is usually controlled by several genes
B
can be influenced by environmental factors
C
follows a normal distribution curve
D
is usually controlled by one or two pair(s) of genes
correct option: d
Users' Answers & Comments50
Acquired characters are
A
received from parents
B
passed to offspring
C
caused by the environment
D
caused by mutation
correct option: c
Users' Answers & Comments