WAEC Agricultural Science 2018 Practical Answers
Read Below For WEAC Agricultural Science Practical Answers
Question 1
Using specimens A,B,C and D, carry out an experiment to show that soil is made up of different particle sizes.
(a) (i) Describe the procedure used in conducting the experiment. [ 5 marks]
(ii) State your observations and results. [ 5 marks]
(b) State one function of each of specimen B and specimen C in the experiment. [2 marks]
(c) State three precautions taken in carrying out the experiment.[3 marks]
OBSERVATION: This question was well attempted by the candidates. In question 1 (a)( i & ii), majority of the candidates could describe the procedure used in conducting the experiment and state the observations and results. Also, in question 1 (b), most candidates were able to state the functions of specimen B(water) and specimen C (sodium carbonate) in the experiment. Further to this, majority of the candidates were able to state the precautions
taken in carrying out the experiment.
Question 2
i. Mention the field operation that could be performed using specimens G, H, I and J. [1 mark]
ii. Name three other equipment that may be added to specimens G, H, I and J to perform the operation you have mentioned in 2(a) (i). [3 marks]
iii. State one precaution that should be taken when using specimen J. [1 mark]
State two uses of each of specimens K and L [4 marks]
State two structural differences between specimens K and L. [4 marks]
Mention two problems that could result from leaving specimen L on the field after use. [2 marks]
OBSERVATION: This question was fairly attempted by many candidates. In 2(a) (i), many candidates could mention the
field operation that could be performed using specimens G (Ranging pole), H (Measuring tape), I (Pin)
and J (Garden line). However, in 2(a) (ii), majority of the candidates could not name the other equipment
that may be added to specimen G (Ranging pole), H (Measuring tape), I (Pin) and J (Garden line) to
perform the operation mentioned in 2(a) (i). Similarly in 2(a) (iii), many candidates were unable to state
the precaution that should be taken when using specimen J (Garden line).
Question 3
a) Identify specimens M, N and 0 by their common names and their scientific names. [6 marks]
(b) (i) Name one pest and one disease that attack the crop from which specimen 0 is obtained. [2 marks']
(ii) State one control measure for each of the pest and disease mentioned [2 marks]
3(b(i). Mention three uses of specimen M. State two methods of preserving specimen N. [3 marks]
(a) Identify specimens M, N and 0 by their common names and their scientific names. [6 marks]
(b) (i) Name one pest and one disease that attack the crop from which specimen 0 is obtained. [2 marks']
(ii) State one control measure for each of the pest and disease mentioned [2 marks]
3(b(i). Mention three uses of specimen M. [3 marks]
State two methods of preserving specimen N. [2 marks]
OBSERVATION: The expected answers include:
Ways by which specimen P is adapted to survive in the host:
Head/scolex has suckers and hooks for firm attachment to host.
Head/scolex for sucking the nutrients and blood from host.
Has many segments/proglottids which have complete reproductive structures. These increase their survival.
They have both male and female reproductive structures, which favours self fertilization.
They secrete chemicals which ensure their freedom from digestive enzymes of host.
Nutrients are absorbed by all surfaces of the body/large surface area.
Formation of cysts around the bladderworm, ensuring the survival of the bladderworm in the reproductive cycle.
The proglottids contain several eggs which increase possibility of survival; even if several perish, many will still survive.
Body covered with tough cuticle which resists digestion by the host.
Question 4
(a) Identify specimens P, Q and R. [2 marks]
(b) Name the part of the host where each of specimens P, Q and Rean be found. [2 marks]
(c) Mention three ways by which specimen P is adapted to survive in the host. [3marks] .
(d) State three effects of specimen Q on the host. [3 marks]
(e) List four diseases transmitted by specimen R. [2 marks]
. (f) State four control measures of specimen R. [4 marks]
OBSERVATION: This question was popular with the candidates. In 4(a) and (b), majority of the candidates could identify
specimens P (Tapeworm), Q (Liver fluke) and R (Tick) and name the part of the host where specimens P
(Intestine of host), Q (Inside the liver/bile duct) and R (skinlhody of host) can be found.
However, in 4(c), many of the candidates could mention ways by which specimen P (Tapeworm) is
adapted to survive in the host. In 4( d), most of the candidates could state the effects of specimen Q (Liver
fluke) on the host. In addition to this, in 4(e) and (f), majority of the candidates were able to list diseases
transmitted by specimen R (Tick) and state control measures of specimen R (Tick).
The expected answers include: Ways by which specimen P is adapted to survive in the host: Head/scolex has suckers and hooks for firm attachment to host. Head/scolex for sucking the nutrients and blood from host. Has many segments/proglottids which have complete reproductive structures. These increase their survival. They have both male and female reproductive structures, which favours self fertilization. They secrete chemicals which ensure their freedom from digestive enzymes of host. Nutrients are absorbed by all surfaces of the body/large surface area. Formation of cysts around the bladderworm, ensuring the survival of the bladderworm in the reproductive cycle. The proglottids contain several eggs which increase possibility of survival; even if several perish, many will still survive. Body covered with tough cuticle which resists digestion by the host.
Other equipment that may be added to specimens G, H, I and J to perform the operation
mentioned in 2(a) (i)
Leveling staff
Abney level
Theodolite
Prismatic compass
Gunter's chain/metric 'chain/engineer's chain
Offset staff/pin
Other equipment that may be added to specimens G, H, I and J to perform the operation mentioned in 2(a) (i)
Leveling staff
Abney level
Theodolite
Prismatic compass
Gunter's chain/metric 'chain/engineer's chain
Offset staff/pin
Precaution that should be taken when using specimen J (Garden line)
Do not drag/rub against rough surfaces/edges
Do not pull too hard when taking measurement to avoid damage/snapping
Properly tie to the pole to avoid accidental release when in use and to ensure accurate readings
Must be straight and horizontal for accurate measurements